Programmable DC Power Supply PSU Series USER MANUAL GW INSTEK PART NO.
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SAFETY INSTRUCTIONS Table of Contents SAFETY INSTRUCTIONS ................................................... 5 GETTING STARTED ........................................................... 9 PSU Series Overview ............................ 10 Appearance .......................................... 14 Theory of Operation ............................. 22 OPERATION .................................................................... 34 Set Up ..................................................
PSU Series User Manual PSU Dimensions ................................ 193 Declaration of Conformity .................. 194 INDEX ............................................................................
SAFETY INSTRUCTIONS SAFETY INSTRUCTIONS This chapter contains important safety instructions that you must follow during operation and storage. Read the following before any operation to insure your safety and to keep the instrument in the best possible condition. Safety Symbols These safety symbols may appear in this manual or on the instrument. WARNING Warning: Identifies conditions or practices that could result in injury or loss of life.
PSU Series User Manual Do not dispose electronic equipment as unsorted municipal waste. Please use a separate collection facility or contact the supplier from which this instrument was purchased. Safety Guidelines General Guideline CAUTION Do not place any heavy object on the PSU. Avoid severe impact or rough handling that leads to damaging the PSU. Do not discharge static electricity to the PSU. Use only mating connectors, not bare wires, for the terminals.
SAFETY INSTRUCTIONS Cleaning the PSU Operation Environment Disconnect the power cord before cleaning. Use a soft cloth dampened in a solution of mild detergent and water. Do not spray any liquid. Do not use chemicals containing harsh material such as benzene, toluene, xylene, and acetone.
PSU Series User Manual Power cord for the United Kingdom When using the power supply in the United Kingdom, make sure the power cord meets the following safety instructions.
GETTING STARTED GETTING STARTED This chapter describes the power supply in a nutshell, including its main features and front / rear panel introduction. After going through the overview, please read the theory of operation to become familiar with the operating modes, protection modes and other safety considerations. PSU Series Overview ....................................................... 10 Series lineup ...................................................................................................
PSU Series User Manual PSU Series Overview Series lineup The PSU series consists of 5 models, covering a number of different current, voltage and power capacities: Model name Voltage Rating1 Current Rating2 Power PSU 6-200 6V 200A 1200W PSU 12.5-120 12.5V 120A 1500W PSU 20-76 20V 76A 1520W PSU 40-38 40V 38A 1520W PSU 60-25 60V 25A 1500W 1Minimum voltage guaranteed to 0.2% of rating voltage. 2Minimum current guaranteed to 0.4% of rating current.
GETTING STARTED Main Features Performance Features Interface High power density: 1500W in 1U Universal input voltage 85~265Vac, continuous operation. Output voltage up to 60V, current up to 200A. Active power factor correction. Parallel master/slave operation with active current sharing. Remote sensing to compensate for voltage drop in load leads. 19" rack mounted ATE applications.
PSU Series User Manual Accessories Before using the PSU power supply unit, check the package contents to make sure all the standard accessories are included. Standard Part number Accessories Description Qty.
GETTING STARTED Optional Accessories Download Other Part number Description PSU-01C Cable for 2 units of PSU-Series in parallel mode connection PSU-01B Bus Bar for 2 units of PSU-Series in parallel mode connection PSU-02C Cable for 3 units of PSU-Series in parallel mode connection PSU-02B Bus Bar for 3 units of PSU-Series in parallel mode connection PSU-03C Cable for 4 units of PSU-Series in parallel mode connection PSU-03B Bus Bar for 4 units of PSU-Series in parallel mode connection PSU-23
PSU Series User Manual Appearance PSU Series Front Panel 1 2 3 4 PSU 40-38 5 Display Area Voltage DC Power Supply Current CV CC 0 - 40 V / 0 - 38A V A VOLTAGE VSR LAN RMT CURRENT ERR DLY ALM ISR Lock/ Local PROT Function Test Set Unlock ALM_CLR M1 M2 M3 M1 M2 Shift M3 RUN Output : Long Push 6 7 8 9 10 11 12 13 1. Power Switch Used to turn the power on/off. 2. USB A Port USB A port for data transfer, loading test scripts etc. 3.
GETTING STARTED 6. Lock/Local Button Lock/Local Unlock (Long push) Used to unlock the front panel buttons. Unlock Button 7. PROT Button Used to lock all front panel buttons other than the Output Button or it switches to local mode. PROT Used to set and display OVP, OCP and UVL. ALM_CLR (Long push) Used to release protection functions that have been activated. ALM_CLR Button 8. Function Button Function Used to configure the various functions. M1 (+Shift) Used to recall the M1 setup.
PSU Series User Manual 11. Shift Button 12. Output Button 13. Output ON LED 16 Shift Output Used to enable the functions that are written in blue characters below certain buttons. Used to turn the output on or off. Lights in green when the output is on.
GETTING STARTED PSU Series Display and Operation Panel Display Area 14 16 15 17 CV CC V A VOLTAGE VSR 18 LAN 19 CURRENT RMT 20 ERR 21 DLY 22 ALM 23 ISR 24 M1 25 M2 26 M3 27 RUN 28 14. Voltage Meter Displays the voltage or the parameter number of a Function parameter. 15. Current Meter Displays the current or the value of a Function parameter. 16. CV LED Lights in green during constant voltage mode. 17. CC LED Lights in green during constant current mode. 18.
PSU Series User Manual 24. ISR LED Lights up when CC Slew Rate Priority is enabled. 25. M1 LED Lights in green when the memory value are being recalled or saved. 26. M2 LED Lights in green when the memory value are being recalled or saved. 27. M3 LED Lights in green when the memory value are being recalled or saved. 28. RUN LED Lights up when a Test Script has been activated.
GETTING STARTED Rear Panel 1 2 ISOLATED PROGRAMMING 4 - 20mA 3 4 5 6 7 8 1 2 ISOLATED PROGRAMMING 0 - 5V / 0 - 10V 3 4 5 6 7 8 9 10 DC OUTPUT ANALOG PROGRAMMING S LS NC LS L N LAN AC 100 240V 47 63Hz 2000VA MAX. REMOTE SENSE OUT 8 1. RS485 / 232 S 7 AC Input IN AC INPUT 6 5 L 4 3 2 1 Wire clamp connector. N AC INPUT 2. DC Output 3. USB 4. LAN Output terminals for 6V to 60V models. USB port for controlling the PSU remotely.
PSU Series User Manual 5. RS 485 / 232 Remote-IN LAN Two different types of cables can be used for RS232 or RS485-based remote control. PSU-232: RS232 cable with DB9 connector kit. PSU-485: RS485 with DB9 connector kit. 6. RS 485 / 232 Remote-OUT LAN RJ-45 connector that is used to daisy chain power supplies with the Remote-IN port to form a communication bus. PSU-485S: Serial link cable with RJ-45 shielded connector. 7. Analog Control 8.
GETTING STARTED 10. Ground Screw TED PROGRAMMING 4 - 20mA 2 3 4 5 6 7 8 OGRAMMING Connector for grounding the output (two positions, shown in red). DC OUTPUT RS485 / 232 L N LAN AC 100 240V 47 63Hz 2000VA MAX.
PSU Series User Manual Theory of Operation The theory of operation chapter describes the basic principles of operation, protection modes and important considerations that must be taken into account before use. Operating Area Description The PSU power supplies are regulated DC power supplies with a high voltage and current output. These operate in CC or CV mode within a wide operating range limited only by the voltage or current output.
GETTING STARTED CC and CV Mode CC and CV mode Description When the power supply is operating in constant current mode (CC) a constant current will be supplied to the load. When in constant current mode the voltage output can vary, whilst the current remains constant. When the load resistance increases to the point where the set current limit (ISET) can no longer be sustained the power supply switches to CV mode. The point where the power supply switches modes is the crossover point.
PSU Series User Manual Conversely the power supply will operate in CC mode when the load resistance is less than the critical resistance. In CC mode the current output is equal to ISET and the voltage output is less than VSET. V RL=RC CV VSET Crossover point RL>RC CC RL
GETTING STARTED Slew Rate Theory The PSU has selectable slew rates for CC and CV mode. This gives the PSU power supply the ability to limit the current/voltage draw of the power supply. Slew rate settings are divided into High Speed Priority and Slew Rate Priority. High speed priority mode will use the fastest slew rate for the instrument. Slew Rate Priority mode allows for user adjustable slew rates for CC or CV mode. The rising and falling slew rate can be set independently.
PSU Series User Manual some time and be potentially hazardous. In addition, bleed resistors also allow for smoother voltage regulation of the power supply as the bleed resistor acts as a minimum voltage load. The bleed resistance can be turned on or off using the configuration settings. Note By default the bleed resistance is on. For battery charging applications, be sure to turn the bleed resistance off as the bleed resistor can discharge the connected battery when the unit is off.
GETTING STARTED Alarms The PSU power supplies have a number of protection features. When one of the protection alarms are tripped, the ALM icon on the display will be lit and the type of alarm that has been tripped will be shown on the display. When an alarm has been tripped the output will be automatically turned off. For details on how to clear an alarm or to set the protection modes, please see page 51. OVP Over voltage protection (OVP) prevents a high voltage from damaging the load.
PSU Series User Manual AC AC Fail. This alarm function is activated when a low AC input is detected. FAN FAIL Fan failure. This alarm function is activated when the fan RPMs drop to an abnormally low level. Shutdown Force Shutdown is not activated as a result of the PSU series detecting an error. It is a function that is used to turn the output off through the application of a signal from the rear-panel analog control connector when an abnormal condition occurs.
GETTING STARTED Considerations The following situations should be taken into consideration when using the power supply. Inrush current When the power supply switch is first turned on, an inrush current is generated. Ensure there is enough power available for the power supply when first turned on, especially if a number of units are turned on at the same time. Pulsed or Peaked loads When the load has current peaks or is pulsed, it is possible for the maximum current to exceed the mean current value.
PSU Series User Manual Reverse Current: Regenerative load When the power supply is connected to a regenerative load such as a transformer or inverter, reverse current will feed back to the power supply. The PSU power supply cannot absorb reverse current. For loads that create reverse current, connect a resistor in parallel to the power supply to bypass the reverse current. This description only applies when the bleed resistance is off.
GETTING STARTED CAUTION Ensure the reverse withstand voltage of the diode is able to withstand 2 times the rated output voltage of the power supply and the forward current capacity can withstand 3 to 10 times the rated output current of the power supply. Ensure the diode is able to withstand the heat generated in the following scenarios. When the diode is used to limit reverse voltage, remote sensing cannot be used.
PSU Series User Manual Grounding The output terminals of the PSU power supplies are isolated with respect to the protective grounding terminal. The insulation capacity of the load, the load cables and other connected devices must be taken into consideration when connected to the protective ground or when floating. Floating As the output terminals are floating, the load and all load cables must have an insulation capacity that is greater than the isolation voltage of the power supply.
GETTING STARTED Grounded output terminal If the positive or negative terminal is connected to the protective ground terminal, the insulation capacity needed for the load and load cables is greatly reduced. The insulation capacity only needs to be greater than the maximum output voltage of the power supply with respect to ground.
PSU Series User Manual OPERATION Set Up ............................................................................. 36 Line Voltage Connection ........................................................................................ 36 Power Up .................................................................................................................. 38 Wire Gauge Considerations.................................................................................... 39 Output Terminals ................
OPERATION Test Scripts ..................................................................... 85 Test Script File Format ........................................................................................... 86 Test Script Settings .................................................................................................. 86 Setting the Test Script Settings .............................................................................. 87 Load Test Script from USB ...............................
PSU Series User Manual Set Up Line Voltage Connection Background Warning The PSU power supplies use a universal power input that can be used with 100 and 240 Vac systems. To connect or replace the power cord (user supplied, specification below), use the procedure below: The following procedure should only be attempted by competent persons. Ensure the AC power cord is not connected to power. Always allow the power supply to fully discharge before disconnecting the AC power cord.
OPERATION 4 L: Black or Brown N: White or Blue GND: Green or Green and Yellow 2-M3x6L Pan Head Screw 3 2 1. Connect the AC power cord wires to the AC input terminals. L N AC 100 240V 47 63Hz 2000VA MAX. Black/Brown Line (L) White/Blue Neutral (N) Green /Green & Yellow Ground ( ) 2. Make sure the sheath is tightened to the lock nut. Ground AC INPUT Line Neutral Installation Screw on locknut 3. Re-install the power cord cover.
PSU Series User Manual Power Up Steps 1. Connect the power cord to the universal power input. Page 36 2. Press the POWER switch on. 3. The power supply will show the Power On settings (Pon) at start up. If no Power On settings are configured, the PSU will recover the state right before the power was last turned OFF. If used for the first time, the default settings will appear on the display. For default configuration settings, see page 183.
OPERATION Wire Gauge Considerations Background Before connecting the output terminals to a load, the wire gauge of the cables should be considered. It is essential that the current capacity of the load cables is adequate. The rating of the cables must equal or exceed the maximum current rated output of the instrument. Recommended wire gauge Wire Gauge Nominal Cross Maximum Current Section 20 0.5 9 18 0.75 11 18 1 13 16 1.5 18 14 2.
PSU Series User Manual used, connect the shield to the chassis via the rear panel ground screw. Even if noise is not a concern, the load and remote sense wires should be twisted-pairs to reduce coupling, which might impact the stability of the power supply. The sense leads should be separated from the power leads.
OPERATION Output Terminals Background Before connecting the output terminals to the load, first consider whether voltage sense will be used, the gauge of the cable wiring and the withstand voltage of the cables and load. The output terminals can be connected to load cables using M8 sized bolts. WARNING Steps Dangerous voltages. Ensure that the power to the instrument is disabled before handling the power supply output terminals. Failing to do so may lead to electric shock. 1. Turn the power switch off.
PSU Series User Manual 5. Connect the positive load cable to the positive output terminal and the negative cable to the negative output terminal. 6. Reattach the output terminal cover. Connection Example Use the included M8-sized bolt set to connect the load cables to the output terminals. Make sure that the connections are tight and that washers and spring washers are used to ensure a good connection.
OPERATION Using the Output Terminal Cover Steps 1. Partially unscrew the 2 screws beside the terminals. 2. Line-up the notches in the cover with the 2 screws. 3. Tighten the screws to secure the cover over the terminals. 2-M3x6L SCRE Removal Reverse the procedure to remove the terminal covers.
PSU Series User Manual Using the Rack Mount Kit Background The PSU series are designed to be directly mounted into 19 inch 1U rack mounts. The PSU can be installed using the sliding mounts (GW Part number: GRM-001). See the GRM-001 manual for installation instructions. Rack mount diagram: Sliding mounts 405 380 Unit = mm The following diagram shows the approximate dimensions of the GRM-001 sliding mounts. These sliding mounts should only be used within racks with a depth of 500mm.
OPERATION How to Use the Instrument Background The PSU power supplies use a novel method of configuring parameter values only using the voltage or current knobs. The knobs are used to quickly edit parameter values at 0.01, 0.1 or 1 unit steps at a time. When the user manual says to set a value or parameter, use the steps below. Example Use the Voltage knob to set a voltage of 10.05 volts. 1. Repeatedly press the Voltage knob until the least significant digit is highlighted.
PSU Series User Manual Note Notice the Set key becomes illuminated when setting the current or voltage. If the voltage or current knobs are unresponsive, press the Set key first.
OPERATION Reset to Factory Default Settings Background Steps The F-88 configuration setting allows the PSU to be reset back to the factory default settings. See page 183 for the default factory settings. 1. Press the Function key. The Function key will light up. Function 2. The display should show F-01 on the top and the configuration setting for F-01 on the bottom. CV CC V A VOLTAGE VSR LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN 3.
PSU Series User Manual View System Version and Build Date Background Steps The F-89 configuration setting allows you to view the PSU version number, build date, keyboard version, analog-control version, kernel build, test command version and test command build date. 1. Press the Function key. The Function key will light up. Function 2. The display should show F-01 on the top and the configuration setting for F-01 on the bottom.
OPERATION F-89 0-XX: Version (1/2) 1-XX: Version (2/2) 2-XX: Build On-Year. (1/2) 3-XX: Build On-Year. (2/2) 4-XX: Build On-Month. 5-XX: Build On-Day. 6-XX: Keyboard CPLD. (1/2) 7-XX: Keyboard CPLD. (2/2) 8-XX: Analog Board CPLD. (1/2) 9-XX: Analog Board CPLD. (2/2) A-XX: Analog Board FPGA (1/2) B-XX: Analog Board FPGA. (1/2) C-XX: Kernel Build On-Year. (1/2) D-XX: Kernel Build On-Year. (2/2) E -XX: Kernel Build On-Month. F-XX: Kernel Build On-Day. G-XX: Test Command Version.
PSU Series User Manual Example Keyboard CPLD Version: 0x030C 6-03: Keyboard CPLD Version. 7-0C: Keyboard CPLD Version. Example Analog CPLD Version: 0x0421 8-04: Analog CPLD Version. 9-21: Analog CPLD Version. Example Analog Board FPGA: 0x0241 A-02: Analog FPGA Version. B-41: Analog FPGA Version. Example Kernel Version: 2013/01/22 C-20: Kernel Build On-Year. D-13: Kernel Build On-Year. E-01: Kernel Build On-Month. F-22: Kernel Build On-Day.
OPERATION Basic Operation This section describes the basic operations required to operate the power supply. Setting OVP/OCP/UVL → from page 51 C.V. priority mode → from page 54 C.C. priority mode → from page 57 Panel lock → page 60 Save/Recall setups → from page 60/61 Voltage Sense → from page 62 Before operating the power supply, please see the Getting Started chapter, page 9.
PSU Series User Manual CV CC V A VOLTAGE VSR LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN Example: OVP alarm Before setting the protection settings: Ensure the load is not connected. Ensure the output is turned off. Note You can use the Function settings (F-13 and F-14) to apply limits to the voltage and current settings, respectively.
OPERATION 2. The OVP protection function will be displayed on the voltage display and the setting will be displayed on the current display. CV CC V A VOLTAGE VSR LAN RMT CURRENT ERR DLY ALM ISR Protection function Choose a Protection Function M2 M3 RUN Protection setting 3. Use the Voltage knob to select a protection function. Range Setting the Protection Level M1 Voltage OVP, OCP, UVL 4. Use the Current knob to set the protection level for the selected function.
PSU Series User Manual Set to C.V. Priority Mode When setting the power supply to constant voltage mode, a current limit must also be set to determine the crossover point. When the current exceeds the crossover point, the mode switches to C.C. mode. For details about C.V. operation, see page 23. C.C. and C.V. mode have two selectable slew rates: High Speed Priority and Slew Rate Priority.
OPERATION 4. Use the Current knob to set the F03 setting. Current Set F-03 to 0 (CV High Speed Priority) or 2 (CV Slew Rate Priority). F-03 0 = CV High Speed Priority 2 = CV Slew Rate Priority 5. Press the Voltage knob to save the configuration setting. ConF will be displayed when it is configuring. Voltage CV CC V A VOLTAGE VSR LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN VSR indicator for CV Slew Rate Priority (F-03=2) 6.
PSU Series User Manual 9. Use the Voltage knob to set the voltage. Note Voltage Notice the Set key becomes illuminated when setting the current or voltage. If the Voltage or Current knobs are unresponsive, press the Set key first. 10. Press the Output key. The Output ON LED becomes lit. Output CV will become illuminated (center) CV CC V A VOLTAGE VSR Note LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN Only the voltage level can be altered when the output is on.
OPERATION Set to C.C. Priority Mode When setting the power supply to constant current mode, a voltage limit must also be set to determine the crossover point. When the voltage exceeds the crossover point, the mode switches to C.V. mode. For details about C.C. operation, see page 23. C.C. and C.V. mode have two selectable slew rates: High Speed Priority and Slew Rate Priority. High Speed Priority will use the fastest slew rate for the instrument while Slew Rate Priority will use a user-configured slew rate.
PSU Series User Manual 4. Use the Current knob to set the F03 setting. Current Set F-03 to 1 (CC High Speed Priority) or 3 (CC Slew Rate Priority) and save. 1 = CC High Speed Priority 3 = CC Slew Rate Priority F-03 5. Press the Voltage knob to save the configuration setting. ConF will be displayed when it is configuring. CV CC V A VOLTAGE LAN RMT Voltage CURRENT ERR DLY ALM ISR M1 M2 M3 RUN ISR indicator for CC Slew Rate Priority (F-03=3) 6.
OPERATION 9. Use the Current knob to set the current. Note Current Notice the Set key becomes illuminated when setting the current or voltage. If the Voltage or Current knobs are unresponsive, press the Set key first. 10. Press the Output key. The Output key becomes illuminated. Output CC will become illuminated (right) CV CC V A VOLTAGE VSR Note LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN Only the current level can be altered when the output is on.
PSU Series User Manual Panel Lock The panel lock feature prevents settings from being changed accidentally. When activated, the Lock/Local key will become illuminated and all keys and knobs except the Lock/Local key and Output key (if active) will be disabled. If the instrument is remotely controlled via the USB/LAN interface, the panel lock is automatically enabled. Activate the panel lock Press the Lock/Local key to active the panel lock. The key will become illuminated.
OPERATION 3. When the setup is saved the unit will beep, the setup will be saved and the memory number will be shown on the display. CV CC V A VOLTAGE VSR LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN Saved setup Recall Setup The PSU has 3 dedicated keys (M1, M2, M3) to recall setups. Recall Setup 1. Press the SHIFT key. The shift key will light blue. 2. Press the desired memory key to recall the desired setup (M1, M2, M3). Shift Function M1 3.
PSU Series User Manual Voltage Sense The PSU power supplies can be operated using local or remote voltage sense. By default the PSU ships configured for local sense. Remote Sense Connector The Remote Sense connector includes a detachable plug to facilitate making the sense connections. The remote sense connector also has a safety cover. Ensure the output is off before handling the remote sense connector. WARNING Use sense cables with a voltage rating exceeding the isolation voltage of the power supply.
OPERATION Remote Sense Cover WARNING Ensure the output is off before handling the remote sense connector. Use sense cables with a voltage rating exceeding the isolation voltage of the power supply. Never connect sensing cables when the output is on. Electric shock or damage to the power supply could result. Always operate the PSU with the remote sense cover. Connector 1. Place the cover over the remote sense connector. 2. Secure the cover with the provided screw.
PSU Series User Manual Local Sense When using local sense, the sensing terminals are connected to the local sense terminals (via the local sense connections) and thus do not compensate for any possible voltage drop that is seen on the load cables. Local sense is only recommended when the voltage drop is of no consequence or for load-current applications. By default, the sense plug is already configured to local sensing.
OPERATION the isolation voltage of the power supply. Never connect sensing cables when the output is on. Electric shock or damage to the power supply could result. Note Single Load Be sure to remove the sense jumpers from the remote sense connector so the unit is not using local sensing. 1. Connect the S+ terminal to the positive potential of the load. Connect the S- terminal to the negative potential of the load. PSU Load Output Input Output Input Page 62 S+ S- 2.
PSU Series User Manual PSU #1 Load Output Input Output Input Page 62 S+ S- PSU #2 Output Output S+ S- 2. Operate the instrument as normal. Page 69 See the Parallel Operation chapter for details. Serial PSU Units 1. a. Connect the 1st S+ terminal to the positive potential of the load. b. Connect the 1st S- terminal to the positive output terminal of the second PSU unit. c. Connect the 2nd S+ terminal to the positive terminal of the second PSU unit. d.
OPERATION PSU #1 Page 62 Load a Output Input Output Input S+ S- b d PSU #2 Output c Output S+ S- 2. Operate the instrument as normal. Page 77 See the Serial Operation chapter for details. Wire Shielding and Load line impedance To help to minimize the oscillation due to the inductance and capacitance of the load cables, use an electrolytic capacitor in parallel with the load terminals. To minimize the effect of load line impedance use twisted wire pairing.
PSU Series User Manual Parallel / Series Operation This section describes the basic operations required to operate the power supply in series or parallel. Operating the PSU series in parallel increases the total current output of the power supply units. When used in series, the total output voltage of the power supplies can be increased. When the units are used in parallel or in series, a number of precautions and limitations apply.
OPERATION Master-Slave Parallel Overview Background When connecting the PSU power supplies in parallel, up to 4 units can be used in parallel and all units must be of the same model with similar output settings. To use the power supplies in parallel, units must be used in a “master-slave” configuration. In the master-slave configuration a “master” power supply controls any other connected “slave” power supplies.
PSU Series User Manual Analog Control Connector Ext-V Ext-R VMON IMON Master Slave Load Slave Slave Limitations Display Only the master unit will display the voltage and current. OVP/ OCP/UVL Slave units follow the settings of the master when OVP/OCP/UVL is tripped on the master unit. Remote monitoring Voltage monitoring (VMON) and current monitoring (IMON) are only supported on the master unit. The IMON current represents the total current of the all the parallelized units.
OPERATION Parallel Calibration The parallel calibration function can be used to offset cables losses. External Voltage and Resistance Control Voltage/Resistance controlled remote control can only be used with the master unit. The full scale current (in parallel) is equivalent to the maximum external voltage or resistance. Internal Resistance For 2 units in parallel, the internal resistance is actually half of the setting value.
PSU Series User Manual Master-Slave Parallel Connection Analog Control Connection To operate the power supplies in parallel with the analog connectors, connect the analog connectors on the master and slave units as shown in the diagrams below.
OPERATION MASTER SLAVE #1 PRL OUT+ 12 9 PRL IN+ A COM 11 8 PRL IN- Status COM1 1 20 A COM OUT ON Status 16 19 OUT ON/OFF CONT Current SUM 13 13 Current Sum Alarm Status 14 14 Alarm_Status Shut_Down 7 7 Shut_Down A COM 20 16 OUT ON Status 1 Status COM1 SLAVE #2 9 PRL IN+ 8 PRL IN- 20 A COM 19 OUT ON/OFF CONT 13 Current Sum 14 Alarm_Status 7 Shut_Down 16 OUT ON Status 1 Status COM1 SLAVE #3 Parallel Output Connection 9 PRL IN+ 8 PRL IN- 20 A COM 1
PSU Series User Manual Example with negative terminal connected to ground Master Output Load Input Output Input Ground Slave #1 Output Output Ground Slave #2 Output Output Ground Steps 1. Ensure the power is off on all power supplies. 2. Choose a master and a slave unit(s). 3. Connect the analog connectors for the master and slave units as shown above. 4. Remove the Output Terminal covers. Page 43 5. Connect the master and slave unit in parallel as shown above. 6. Reattach the terminal covers.
OPERATION Master-Slave Parallel Operation Master-Slave Configuration Steps Before using the power supplies in parallel, the master and slave units need to be configured. 1. Configure the OVP, OCP and ULV Page 51 settings for the master unit. 2. For each unit, hold the Function key while turning the power on to enter the power on configuration settings.
PSU Series User Manual Note Configuration settings can be checked on both the master and slave units by pressing the Function key and checking F-93. Only the Master OVP, OCP and UVL settings are used for protection. Slave protection levels are disregarded. OHP works independently for each unit. Master-Slave Operation Steps Only operate the power supplies in parallel if the units are configured correctly. 1. Turn on the master and slave units. The slave unit(s) will show a blank display.
OPERATION Master-Slave Parallel Calibration Master-Slave Configuration The F-16 function setting can be used to calibrate the output of PSU units connected in parallel. If you feel the accuracy is not good enough when you measure the accuracy in parallel mode, the parallel calibration can be used to get better measurement accuracy. Steps 1. Short all the terminals together. This is best accomplished by connecting the master and all the slave units in parallel and then shorting the output terminals.
PSU Series User Manual 5. On the master unit, set F-16 (Auto Page 102 Calibration Parallel Control) to 2 to turn on the parallel calibration. Calibration will begin immediately. 6. Whilst calibration is being performed, WAIT will be displayed on the master screen. Calibration will take a few moments. CV CC V A VOLTAGE VSR LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN 7. When the calibration has finished, OK will be displayed on the master screen.
OPERATION Master-Slave Series Overview Background When connecting PSU power supplies in series, up to 2 units can be used in series and all units must be of the same model. When operated in series, the power supplies can be used to increase the voltage output or setup the power supplies to output both positive and negative polarities. Unlike with the parallel operation, the series operation does not require any special configuration as each power supply is operated and controlled individually.
PSU Series User Manual OVP/OCP/ULV OVP, OCP and ULV level for each unit must be set separately. The OVP and OCP protections are tripped independently on the master and slave. Remote monitoring Voltage monitoring (VMON) and current monitoring (IMON) should be performed on both units. The VMON voltage represents the voltage of that particular unit. Remote Sense Please see the voltage sense chapter for details, page 62.
OPERATION Output Voltage/ Output Current Model PSU 6-200 PSU 12.5-120 PSU 20-76 PSU 40-38 PSU 60-25 Single unit 6V 200A 12.5V 120A 20V 76A 40V 38A 60V 25A 2 units 12V 200A 25V 120A 40V 76A 80V 38A 120V 25A Series Connection If using the PSU in series, please be aware that each unit is acts independently and thus there are no special communication buses for serial connections.
PSU Series User Manual Series Connection to Output Positive and Negative Polarity Unit #1 Output Load Input Output COM Input Ground Unit #2 Output Output Ground Note: The output reference ground (COMMON) can be grounded at the power supply side instead of the load, depending on the requirements. Local sensing should be used in this configuration. Caution Steps When connecting the units in series, diodes should be connected across each output to prevent reverse voltage. 1.
OPERATION Page 39 Ensure load cables have sufficient current capacity. Note Series Operation Series Configuration Before using the power supplies in series, the master and slave units need to be configured. 1. Configure the OVP, OCP and ULV Page 51 settings for each unit. 2. For each unit, hold the Function key while turning the power on to enter the power on configuration settings.
PSU Series User Manual Series Operation Only operate the power supplies in series if the units are configured correctly. 1. Turn on both units. When connected in series unit will only show the voltage and current of their own unit. Unit #1 CV CC V A VOLTAGE VSR LAN RMT CURRENT ERR DLY Unit #2 ALM ISR M1 M2 M3 CV CC V A VOLTAGE VSR LAN RMT RUN CURRENT ERR DLY ALM ISR M1 M2 M3 RUN 2. Operation of both units is the same Page 51 as for a single unit.
OPERATION Test Scripts This section describes how to use the Test function to run, load and save test scripts for automated testing. The Test function is useful if you want to perform a number of tests automatically. The PSU test function can store ten test scripts in memory. Each test script is programmed in a scripting language. For more information on how to create test scripts, please contact GW Instek.
PSU Series User Manual Test Script File Format Background The test files are saved in *.tst file format. Each file is saved as tXXX.tst, where XXX is the save file number 001~010. Test Script Settings Test Run Runs the chosen test script from the internal memory. A script must first be loaded into the internal memory before it can be run. See the test function Test Save, below. The script will run as soon as the test function is started.
OPERATION Setting the Test Script Settings Steps The test script settings (T-01~T-10) are set with the Test key. 1. Press the Test key. The Test key will light up. TEST 2. The display will show T-01 on the left and the memory no. for T-01 on the right. The middle of the display will indicate if the desired file is available in memory or not. Y indicates Yes, N indicates No. Available Y/N CV CC V A VOLTAGE VSR LAN RMT CURRENT ERR DLY ALM ISR Test number M1 M2 M3 RUN Test setting 3.
PSU Series User Manual 4. Rotate the Current knob to choose a memory number. (Excluding T05) Range 1~10 5. Press the Voltage knob to complete the setting. Exit Current Press the Test key again to exit the Test settings. The Test key light will turn off. Voltage TEST Load Test Script from USB Overview Steps 88 Before a test script can be run, it must first be loaded into a one of the 10 memory save slots.
OPERATION 2. Turn on the power. MS ON (Mass Storage) will be displayed on the screen after a few seconds if the USB drive is recognized. Conversely, MS OFF will be displayed if removed. CV CC V A VOLTAGE VSR Note LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN If the USB drive is not recognized, check to see that the function settings for F-20 = 1 (page 102). If not, reinsert the USB flash drive. 3. Configure T-02 (Test Copy) to 1~10 Page 87 (save memory slot) T-02 range 1~10 4.
PSU Series User Manual 2. Configure T-01 (Run Test) to 1~10 Page 87 (save memory slot no. to run) T-01 range 1~10 3. The test script will automatically start to run. Note Error messages: If you try to run a test script from an empty memory location “Err 003” will be displayed on the display. CV CC V A VOLTAGE VSR Stop a Test LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN To stop (abort) a running test at any time, press the Test key.
OPERATION 2. Turn on the power. MS (Mass Storage) will be displayed on the screen after a few seconds if the USB drive is recognized. CV CC V A VOLTAGE VSR Note LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN If the USB drive is not recognized, check to see that the function settings for F-20 = 1 (page 101). If not, reinsert the USB flash drive. 3. Configure T-03 (Test Export) to 1~10 (save memory slot) Page 87 T-03 range 1~10 4. The script will now be copied to the USB flash drive.
PSU Series User Manual 2. The test script will be removed from the internal memory. OK will be displayed when completed. Note Error messages: If you try to remove a test script from an empty memory location “Err 003” will be displayed on the display.
CONFIGURATION CONFIGURATION Configuration Overview ................................................... 94 Configuration Table ................................................................................................ 94 Normal Function Settings ...................................................................................... 99 Interface Configuration Settings .......................................................................... 102 USB / GPIB Settings......................................
PSU Series User Manual Configuration Overview Configuration of the PSU power supplies is divided into five different configuration settings: Normal Function, USB/GPIB, LAN, UART, System Configuration Settings, Power ON Configuration and Special Function Settings. Power ON Configuration differs from the other settings in that the settings used with Power ON Configuration settings can only be set during power up. The other configuration settings can be changed when the unit is already on.
CONFIGURATION Falling voltage slew rate F-05 0.001~0.06V/msec (PSU 6-200) 0.001~0.125V/msec (PSU 12.5-120) 0.001~0.2V/msec (PSU 20-76) 0.001~0.4V/msec (PSU 40-38) 0.001~0.6V/msec (PSU 60-25) Rising current slew rate F-06 0.001~2A/msec (PSU 6-200) 0.001~1.2A/msec (PSU 12.5-120) 0.001~0.76A/msec (PSU 20-76) 0.001~0.38A/msec (PSU 40-38) 0.001~0.25A/msec (PSU 60-25) Falling current slew rate F-07 0.001~2A/msec (PSU 6-200) 0.001~1.2A/msec (PSU 12.5-120) 0.001~0.76A/msec (PSU 20-76) 0.001~0.
PSU Series User Manual Lock Mode USB/GPIB Settings Show front panel USB status Show rear panel USB status F-19 0:Lock Panel, Allow Output OFF 1:Lock Panel, Allow Output ON/OFF F-20 0 = None, 1 = Mass Storage F-21 0 = None, 1 = Linking to PC Setup rear USB Speed F-22 GPIB Address GPIB Enable/Disable Show GPIB available status F-23 F-24 0 = Disable USB, 1 = Full Speed, 2 = Auto Detect Speed 0 ~ 30 0 = Disable GPIB, 1 = Enable GPIB F-25 0 = No GPIB, 1 = GPIB is available SCPI Emulation F-26 0 =
CONFIGURATION Socket Server Enable/Disable Web Server Enable/Disable Web Password Enable/Disable Web Enter Password UART Settings F-57 F-59 F-60 F-61 UART Mode F-70 UART Baud Rate F-71 UART Data Bits UART Parity UART Stop Bit UART TCP UART Address (For TDK) System Settings F-72 F-73 F-74 F-75 F-76 Factory Set Value F-88 Show Version F-89 0 = Disable, 1 = Enable 0 = Disable, 1 = Enable 0 = Disable, 1 = Enable 0000~9999 0 = Disable UART, 1 = RS232, 2 = RS485 0 = 1200, 1 = 2400, 2 = 4800, 3 = 9600,
PSU Series User Manual CC Control F-91 Output Status when Power ON F-92 Master/Slave Configuration F-93 External Output Logic F-94 Monitor Voltage Select F-96 Control Range F-97 External Output Control F-98 Function Special Function Settings* Calibration F-00 *Note 98 0 = Control by Local 1 = Control by External Voltage 2 = Control by External Resistor Rising 3 = Control by External Resistor Falling 4 = Control by Isolated Board 0 = Safe Mode (Always OFF), 1 = Force Mode (Always ON), 2 = Auto Mode
CONFIGURATION Normal Function Settings Output ON Delay Time Delays turning the output on for a designated amount of time. The Delay indicator will light when the Delay time is not 0. Note: The Output ON Delay Time setting has a maximum deviation (error) of 20ms. The Output ON Delay Time setting is disabled when the output is set to external control. CV CC V A VOLTAGE VSR LAN RMT CURRENT ERR F-01 Output OFF Delay Time DLY ALM ISR M1 M2 M3 RUN 0.00s~99.
PSU Series User Manual V-I Mode Selects High Speed Priority or Slew Rate Priority for CV or CC mode. The voltage or current slew rate can only be edited if CC/CV Slew Rate Priority is selected. The ISR indicator will be lit for CC Slew Rate Priority and the VSR indicator will be lit for CV Slew Rate Priority. Note: CC and CV Slew Rate Priority mode are disabled when voltage/current output is set to external control.
CONFIGURATION Falling Current Slew Rate Sets the falling current slew rate. Only applicable if V-I Mode is set to CC Slew Rate Priority. F-07 0.001 ~ max. A/msec Internal Resistance Settings Sets the internal resistance of the power supply. F-08 0.000Ω ~ X.XXXΩ (Where X.XXX = Rating Voltage / Rating Current) Bleeder Control Bleeder control turns ON/OFF the bleeder resistor. Bleeder resistors discharge the filter capacitors after power is turned off as a safety measure.
PSU Series User Manual F-14 0 = OFF 1 = ON Display Memory Parameter Displays which memory setting is recalled (M1, M2 or M3) when recalling a setup. F-15 0 = OFF, 1 = ON Auto Calibration Parallel Control This function performs offset calibration for parallel control. There must be a short between each unit before starting the calibration. See page 77 for details.
CONFIGURATION Show Rear Panel USB Status Setup Rear USB Speed Displays the rear panel USB-B port state. This setting is not configurable. F-21 0 = None, 1 = Linking to PC Sets the rear panel USB speed or turns the rear USB port off. 0 = Disable USB, 1 = Full Speed, F-22 2 = Auto Detect Speed GPIB Address Sets the GPIB address. F-23 0 ~ 30 GPIB Disable/Enable Enable or disables the GPIB port. 0 = Disable GPIB, 1 = Enable F-24 GPIB Show GPIB available Status Shows the status of the GPIB option port.
PSU Series User Manual DHCP Turns DHCP on or off. F-37 0 = OFF, 1 = ON IP Address-1~4 Sets the default IP address. IP address 1~4 splits the IP address into four sections. (F-39 : F-40 : F-41 : F-42) (0~255 : 0~255 : 0~255 : 0~255) Subnet Mask 1~4 Sets the subnet mask. The subnet mask is split into four parts. (F-43 : F-44 : F-45: F-46) (0~255 : 0~255 : 0~255 : 0~255) Gateway 1~4 Sets the gateway address. The gateway address is split into 4 parts.
CONFIGURATION UART Settings UART Mode Sets the UART mode or disables UART. F-70 0 = Disable UART, 1 = RS232, 2 = RS485 UART Baud Rate Sets the UART baud rate. F-71 0 = 1200, 1 = 2400, 2 = 4800, 3 = 9600, 4 = 19200, 5 = 38400, 6 = 57600, 7 = 115200 UART Data Bits Sets the number of data bits. F-72 0 = 7 bits, 1 = 8 bits UART Parity Sets the parity. F-73 0 = None, 1 = Odd, 2 = Even UART Stop Bit Sets the number of stop bits.
PSU Series User Manual System Settings Factory Default Configuration Show Version 106 Returns the PSU to the factory default settings. See page 183 for a list of the default settings. F-88 0 = None, 1 = Factory Default. Displays the PSU version number, build date, keyboard CPLD, analog board CPLD, analog board FPGA, kernel build date, test command version and test command build date.
CONFIGURATION Power On Configuration Settings CV Control Sets the constant voltage (CV) control mode between local and external voltage/resistance control. For external voltage control, see page 118 (External Voltage Control of Voltage Output) and page 123 (External Resistance Control of Voltage Output). For Isolated control, see page 140 for details.
PSU Series User Manual F-92 0 = Safe Mode (Always OFF), 1 = Force Mode (Always ON), 2 = Auto Mode (Status before last time Power OFF) Master/Slave Configuration Sets the power supply as master or slave. See the parallel/series operation for details, page 68. F-93 0 = Independent 1 = Master with 1 slave in parallel 2 = Master with 2 slaves in parallel 3 = Master with 3 slaves in parallel 4 = Slave (parallel) External Output Logic Sets the external logic as active high or low for analog control pin 19.
CONFIGURATION Special Function Special Function The special function setting is used to access calibration, firmware updates and other special functions. The special function setting has a password that is used to access the special function menu. The password used determines which function is accessed. Please see your distributor for details.
PSU Series User Manual CV CC V A VOLTAGE VSR LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN 3. Rotate the Voltage knob to change the F setting. F-00~F-61, F-70~F-76, F-88~F-98 Range 4. Use the Current knob to set the parameter for the chosen F setting. Press the Voltage knob to save the configuration setting. ConF will be displayed when it is configuring.
CONFIGURATION Setting Power On Configuration Settings Background The Power On Configuration settings can only be changed during power up to prevent the configuration settings being inadvertently changed. Ensure the load is not connected. Ensure the power supply is off. Steps 1. Hold the Function key whilst turning the power on.
PSU Series User Manual Press the Voltage knob to save the configuration setting. ConF will be displayed when it is configuring. CV CC V A VOLTAGE VSR Exit 112 LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN Cycle the power to save and exit the configuration settings.
ANALOG CONTROL ANALOG CONTROL The Analog Control chapter describes how to control the voltage or current output using an external voltage or resistance, monitor the voltage or current output as well as remotely turning off the output or shutting down the power supply. Analog Remote Control Overview ................................... 114 Analog Control Connector Overview ................................................................. 115 External Voltage Control of Voltage Output ......................
PSU Series User Manual Analog Remote Control Overview The PSU power supply series have a number of analog control options. The Analog Control connectors are used to control output voltage and current using external voltage or resistance. The power supply output can also be controlled using external switches. There is also an isolated analog control option. The Isolated analog connector is used to control the output voltage and current using an isolated external voltage or current source.
ANALOG CONTROL Analog Control Connector Overview Overview The Analog Control Connector is a 25 pin connector that can be used with the ARC (analog remote control) kit for wiring connections. The connector is used for all analog remote control. The pins used determine what remote control mode is used. Pin Assignment 1 25 Pin name Pin number Description Status COM1 1 This is the common line for the status signal pins 2 to 3 and 14 to 16.
PSU Series User Manual Alarm Clear 10 Alarm clear line. Alarms are cleared when a low level TTL signal is applied. A COM 11 This is the common line for the external signal pins 7 to 10, 12, 13, 19, 21, 24, and 25. It is connected internally to the negative output. PRL OUT+ 12 Positive output line for master-slave parallel operation. Current Sum 13 Current signal line for master-slave parallel operation.
ANALOG CONTROL EXT-V/R CC CONT 21 This line uses an external voltage or resistance to control the output current. External voltage control (F-91: 1); External resistor control (F-91: 2, F-91: 3). 0 to 5V or 0 to 5kΩ; 0 % to 100 % of the rated output current (F-97: 0). 0 to 10V or 0 to 10kΩ; 0 % to 100 % of the rated output current (F-97: 1). EXT-V/R CV CONT 22 This line uses an external voltage or resistance to control the output voltage.
PSU Series User Manual External Voltage Control of Voltage Output Background External voltage control of the voltage output is accomplished using the analog control connector on the rear panel. There are two external voltage control ranges, 0~5V and 0~10V, depending on the F-97 configuration. See page 108 for details.
ANALOG CONTROL Connection- alt. shielding If the wire shield needs to be grounded at the voltage source (EXT-V), then the shield cannot also be grounded at the negative (-) terminal output of the PSU power supply. This would short the output. EXT-V PSU 22 + - Analog connector 23 2 core shielded wire or twisted pair Panel operation Output Terminal Pin23 → EXT-V(-) Pin22 → EXT-V(+) Wire shield → EXT-V ground (GND) 1. Connect the external voltage according to the connection diagrams above.
PSU Series User Manual Note The input impedance for external voltage control is 1MΩ. Use a stable voltage supply for the external voltage control. Note CV and CC Slew Rate Priority are disabled for V-I mode (F-03) when using external voltage control. See the normal function settings on page 99. CAUTION Ensure no more than 10.5V(F-97 = 1) or 5.25 (F-97 = 0) volts are input into the external voltage input. Ensure the voltage polarity is correct when connecting the external voltage.
ANALOG CONTROL External Voltage Control of Current Output Background External voltage control of the current output is accomplished using the analog control connector on the rear panel. There are two external voltage control ranges, 0~5V and 0~10V, depending on the F-97 configuration. See page 108 for details.
PSU Series User Manual Connection- alt. shielding If the wire shield needs to be grounded at the voltage source (EXT-V), then the shield cannot also be grounded at the negative (-) terminal output of the PSU power supply. This would short the output. EXT-V PSU 21 + - Analog connector 23 2 core shielded wire or twisted pair Steps Output Terminal Pin23 → EXT-V (-) Pin21 → EXT-V (+) Wire shield → EXT-V ground (GND) 1. Connect the external voltage according to the connection diagrams above.
ANALOG CONTROL Note The input impedance for external voltage control is 1MΩ. Use a stable voltage supply for the external voltage control. Note CV and CC Slew Rate Priority are disabled for V-I mode (F-03) when using external voltage control. See the normal function settings on page 99. CAUTION Ensure the voltage polarity is correct when connecting the external voltage. Ensure no more than 10.5V(F-97 = 1) or 5.25 (F-97 = 0) volts are input into the external voltage input.
PSU Series User Manual Falling: For 10kΩ~0kΩ: Output voltage = full scale voltage × ([10-external resistance]/10) For 5kΩ~0kΩ: Output voltage = full scale voltage × ([5-external resistance]/5) Note The falling resistance configuration is recommended for safety reasons. In the event that the cables become accidentaly disconnected (high Ω), the voltage output will drop to zero. Under similar circumstances using the rising resistance configuaration, an unexpectedly high voltage would be output.
ANALOG CONTROL Be sure to cycle the power after the power on configuration has been set. 3. Press the Function key and confirm the new configuration settings (F90=2 or 3). 4. Press the Output key. The voltage can now be controlled with the External resistance. Note Function Output Ensure the resistor(s) and cables used exceed the isolation voltage of the power supply. For example: insulation tubes with a withstand voltage higher than the power supply can be used.
PSU Series User Manual 5kΩ~0kΩ/10kΩ~0kΩ. Rising: For 0kΩ~10kΩ: Output current = full scale current × (external resistance/10) For 0kΩ~5kΩ: Output current = full scale current × (external resistance/5) Falling: For 10kΩ~0kΩ: Output current = full scale current × ([10-external resistance]/10) For 5kΩ~0kΩ: Output current = full scale current × ([5-external resistance]/5) Note The falling resistance configuration is recommended for safety reasons.
ANALOG CONTROL Steps 1. Connect the external resistance according to the connection diagrams above. Page 111 2. Set the F-91 (CC Control) configuration settings to 2 for external resistor rising or to 3 for external resistor falling. Be sure to cycle the power after the power on configuration has been set. 3. Press the Function key and confirm the new configuration settings (F91 = 2 or 3). 4. Press the Output key. The current can now be controlled with the External resistance.
PSU Series User Manual External Control of Output Background The output can be turned on or off externally using a switch. The analog control connector can be set to turn the output on from a high or low signal. The voltage across pins 19 and 20 are internally pulled up to +5V ±5% @ 500uA with 10kΩ pull-up resistor. A short (closed switch) produces a low signal. When set to High = On, the output is turned on when the pins 19-20 are open. When Low = On, the output is turned on when pins 19-20 are shorted.
ANALOG CONTROL Set F-94 (External output logic) in Page 111 the power on configuration settings to 0 (High = On) or 1 (Low = On) and set F-98 (External output control function) to 1(On). Be sure to cycle the power after setting the power on configuration settings. 2. Press the Function key and confirm the new configuration settings (F94 = 0 or 1 and F-98=1). Function 3. The switch is now ready to set the output on or off.
PSU Series User Manual Note Messages: If F-94 = 0 (High = on) and pin 19 is low (0) “MSG 001” will be displayed on the display. If F-94 = 1 (Low = on) and pin 19 is high (1) “MSG 002” will be displayed on the display.
ANALOG CONTROL External control of Shutdown Background Connection The output of the power supplies can be configured to shut down via an external switch. The voltage across pins 7 and 20 are internally pulled to +5V ±5% @ 500uA with 10kΩ pull-up resistor. The output is turned off when a low TTL level signal is applied. Switch PSU 7 Analog connector 20 2 core shielded wire or twisted pair Steps Output Terminal Pin7→ Switch Pin20 → Switch Wire shield → negative (-) output terminal 1.
PSU Series User Manual Note When using a switch over long distances, please use a switch relay to extend the line from the coil side of the relay. Switch Relay Line extention 7 Analog connector 20 Output If a single switch control is to be used for multiple Terminal units, please isolate each instrument. This can be achieved by using a relay. Warning 132 Ensure the cables and switch used exceed the isolation voltage of the power supply.
ANALOG CONTROL Remote Monitoring The PSU power supplies have remote monitoring support for current and voltage output. They also support monitoring of operation and alarm status. External monitoring of output voltage and current → from page 133 External monitoring of operation mode and alarm status → from page 136 External Trigger In/Out → from page 139 External Voltage and Current Monitoring Background The analog connector is used to monitor the current (IMON) or voltage (VMON) output.
PSU Series User Manual Set F-96 (Monitor Voltage Select) Page 111 in the power on configuration settings to 0 (5V) or 1 (10V). Be sure to cycle the power after setting the power on configuration settings. 3. Press the Function key and confirm the new configuration settings (F-96 = 0 or 1). Function 4. An external DMM can now be used to monitor the voltage or current output.
ANALOG CONTROL Note Maximum current is 5mA. Ensure the sensing circuit has an input impedance greater than 1MΩ. The monitor outputs are strictly DC and should not be used to monitor analog components such as transient voltage response or ripple etc. CAUTION Ensure IMON(pin 24) and VMON(pin 25) are not shorted together. This may cause damage to the unit.
PSU Series User Manual External Operation and Status Monitoring Background The analog control connector can also be used to monitor the status operation and alarm status of the instrument. The pins are isolated from the power supply internal circuitry by photo couplers. Status Com1 (Pin 1) and Status Com2 (Pin 5) are photo coupler emitter outputs, whilst pins 2~3, 14~17 are photo coupler collector outputs. A maximum of 30V and 8mA can be applied to each pin.
ANALOG CONTROL Timing diagrams Below are 4 example timing diagrams covering a number of scenarios. Note that pins 14~16 are all active low. CV MODE: Output turned on The diagram below shows the timing diagram when the output is turned on when the PSU is set to CV mode. H CV status L H CC status L H Output status L CV MODE: Output turned off The diagram below shows the output status lines when the output is turned off in CV mode.
PSU Series User Manual CC MODE: Output turned on The diagram below shows the timing diagram when the output is turned on when the PSU is set to CC mode. H CV status L H CC status L H Output status L CC MODE: Output turned off The diagram below shows the output status lines when the output is turned off in CC mode.
ANALOG CONTROL External Trigger In/Out Background Pin 4 is used for the external trigger input and pin 17 is used as the trigger output. Pin 5 is the common for both pins. Name and Pin Description STATUS 5 Common (photo coupler COM2 emitter) for trigger pins 4, 17. TRIG IN 4 External trigger input TRIG OUT 17 The TRIG OUT signal is held high by an internal 330Ω resistor. The trigger output is pulsed low for each trigger.
PSU Series User Manual Isolated Analog Control Option The PSU power supplies can use the isolated analog connector for external control and remote monitoring.
ANALOG CONTROL Isolated Analog Control Option Specifications 0~5V / 0~10V Option (PSU-ISO-V) External voltage control output voltage External voltage control output current Temperature coefficient Programming input impedance Absolute maximum voltage Output voltage monitor Output current monitor Monitor output impedance Accuracy and linearity: ±1% of rated output voltage Accuracy and linearity: ±1% of % rated output current 100ppm/ºC of rated voltage or ppm/ºC current, after a 30 minute warm-up % Ohm 1M
PSU Series User Manual Isolated Analog Control Option Overview Overview Note Pin Assignment Pin name SHIELD +VPROG_ISO +IPROG_ISO GND_ISO GND_ISO +VMON_ISO +IMON_ISO Shield 142 The Isolated Analog Connectors are 8 pin sockets that are optically isolated from the power supply, allowing inputs with ground references that differ to the power supply. The isolated options include either an isolated voltage (0~5V/0~10V) interface or an isolated current (4~20mA) interface.
ANALOG CONTROL Isolated External Voltage Control of Voltage Output Background Voltage control of the voltage output uses the isolated voltage option (PSU-ISO-V).
PSU Series User Manual Connection- alt. shielding If the wire shield needs to be grounded at the voltage source (EXT-V), then it can be connected as shown below. EXT-V PSU + 2 - 4 2 core shielded wire or twisted pair Panel operation Isolated Voltage Option Output Terminal Pin4(GND_ISO) → EXT-V (-) Pin2(+VPROG_ISO) → EXT-V (+) EXT-V ground (GND) → Wire shield 1. Connect the external voltage according to the connection diagrams above. Page 111 2.
ANALOG CONTROL 5. Press the Output key. The voltage can now be controlled with the isolated external voltage control. Note Output The input impedance for isolated external voltage control is 1MΩ. Use a stable voltage supply for the external voltage control. Note CV and CC Slew Rate Priority are disabled for V-I mode (F-03) when using external voltage control. See the normal function settings on page 99. CAUTION Ensure the voltage polarity is correct when connecting the external voltage.
PSU Series User Manual Isolated External Voltage Control of Current Output Background Voltage control of the current output uses the isolated voltage option (PSU-ISO-V).
ANALOG CONTROL Connection- alt. shielding If the wire shield needs to be grounded at the voltage source (EXT-V), then it can be connected as shown below. EXT-V PSU + 3 - 4 2 core shielded wire or twisted pair Steps Isolated Voltage Option Output Terminal Pin4(GND_ISO) → EXT-V (-) Pin3(+IPROG_ISO) → EXT-V (+) Wire shield → EXT-V ground (GND) 1. Connect the external voltage according to the connection diagrams above. Page 111 2.
PSU Series User Manual 5. Press the Output key. The current can now be controlled with the isolated external voltage control. Note Output The input impedance of isolated external voltage control is 1MΩ. Use a stable voltage supply for the external voltage control. Note CV and CC Slew Rate Priority are disabled for V-I mode (F-03) when using external voltage control. See the normal function settings on page 99. CAUTION Ensure the voltage polarity is correct when connecting the external voltage.
ANALOG CONTROL Connection When connecting the external current source to the isolated analog option, use shielded or twisted paired wiring. EXT-I PSU 2 4 Isolated Current Option 1or8 2 core shielded wire or twisted pair Connection- alt. shielding Output Terminal Pin4(GND_ISO) → EXT-I (-) Pin2(+VPROG_ISO) → EXT-I (+) Pin 1 or 8 (Shield) → Wire shield If the wire shield needs to be grounded at the current source (EXT-I), then it can be connected as shown below.
PSU Series User Manual Page 111 2. Set the F-90 power on configuration setting to 4 (Control by Isolated Board). 3. Set the F-97 power on configuration setting to 1. Be sure to cycle the power after the power on configuration has been set. 4. Press the Function key and confirm the new configuration settings (F90=4, F-97=1). 5. Press the Output key. The voltage can now be controlled with the isolated external current control.
ANALOG CONTROL Isolated External Current Control of Current Output Background Current control of the current output uses the isolated current option (PSU-ISO-I). A current of 4~20mA is used to control the full scale current of the instrument, where: Output current = full scale current × ((external current - 4mA)/16mA) Connection When connecting the external current source to the isolated current option, use shielded or twisted paired wiring.
PSU Series User Manual Connection- alt. shielding If the wire shield needs to be grounded at the current source (EXT-I) , then it can be connected as shown below. EXT-I PSU 3 4 2 core shielded wire or twisted pair Steps Isolated Current Option Output Terminal Pin4(GND_ISO) → EXT-I (-) Pin3(+IPROG_ISO) → EXT-I (+) Wire shield → EXT-I ground (GND) 1. Connect the external current according to the connection diagrams above. Page 111 2.
ANALOG CONTROL Note Use a stable current source for the external current control. Note CV and CC Slew Rate Priority are disabled for V-I mode (F-03) when using external voltage control. See the normal function settings on page 99. CAUTION Ensure the polarity is correct when connecting the external voltage. Ensure no more than 21mA are input into the external current input.
PSU Series User Manual PSU VMON Connection DMM V MON 0→10V or 0→5V or 4mA→ 20mA 6 5 Output Terminal Pin6 (+VMON_ISO) → Pos (+) Pin5 (GND_ISO) → Neg (-) IMON Connection PSU DMM I MON 0→10V or 0→5V or 4mA→ 20mA Steps Isolated Voltage or Current Option 7 5 Isolated Voltage or Current Option Output Terminal Pin7(+IMON_ISO) → Pos (+) Pin5(GND_ISO) → Neg (-) 1.
ANALOG CONTROL 4. Press the Function key and confirm the new configuration settings (F96=0 or 1). Function 5. The current or voltage output can now be monitored using the isolated voltage or current option. Note The monitor outputs are strictly DC and should not be used to monitor analog components such as transient voltage response or ripple etc.
PSU Series User Manual COMMUNICATION INTERFACE This chapter describes basic configuration of IEEE488.2 based remote control. For a command list, refer to the programming manual, downloadable from GW Instek website, www.gwinstek.com Interface Configuration .................................................. 157 USB Remote Interface .......................................................................................... 157 Configuration ....................................................................
COMMUNICATION INTERFACE Interface Configuration USB Remote Interface Configuration USB Configuration Steps PC side connector Type A, host PSU side connector Rear panel Type B, slave Speed 1.1/2.0 (full speed/high speed) USB Class CDC (communications device class) 1. Connect the USB cable to the rear panel USB B port. 2. Change the Rear panel-USB (F-22) Page 109 setting to 2 (Auto Detect Speed) or 1 (USB Full Speed).
PSU Series User Manual Function Check Functionality check Invoke a terminal application such as Realterm. To check the COM port No., see the Device Manager in the PC. For WinXP; Control panel → System → Hardware tab. Run this query command via the terminal application after the instrument has been configured for USB remote control (page 157). *idn? This should return the Manufacturer, Model number, Serial number, and Firmware version in the following format. GW-INSTEK,PSU40-38,TW123456,T0.01.
COMMUNICATION INTERFACE GPIB Remote Interface Configuration To use GPIB, the optional GPIB option (GW Instek part number: PSU-GPIB) must be installed. This is a factory installed option and cannot be installed by the end-user. Only one GPIB address can be used at a time. Configure GPIB 1. Ensure the PSU is off before proceeding. 2. Connect a GPIB cable from a GPIB controller to the GPIB port on the PSU. 3. Turn the PSU on. 4. Press the Function key to enter the Page 109 Normal configuration settings. 5.
PSU Series User Manual 7. The RMT indicator will turn on when a remote connection has been established.
COMMUNICATION INTERFACE Functionality check 1. Start the NI Measurement and Automation Explorer (MAX) program. Using Windows, press: Start>All Programs>National Instruments>Measurement & Automation 2. From the Configuration panel access; My System>Devices and Interfaces>GPIB 3. Press Scan for Instruments.
PSU Series User Manual 4. Select the device (GPIB address of PSU) that now appears in the System>Devices and Interfaces > GPIB-USB-HS “GPIBX” node. 5. Click on the VISA Properties tab on the bottom. 6. Click Open Visa Test Panel. 6 4 5 7. Click on Configuration. 8. Click on the GPIB Settings tab and confirm that the GPIB settings are correct. 7 8 9. Click on the I/O Settings tab. 10.
COMMUNICATION INTERFACE check box is checked, and the terminal character is \n (Value: xA). 11. Click Apply Changes. 9 10 11 12. Click on Input/Output. 13. Click on the Basic/IO tab. 14. Enter *IDN? in the Select or Enter Command drop down box. 15. Click Query. 16. The *IDN? query will return the Manufacturer, model name, serial number and firmware version in the dialog box. GW-INSTEK,PSU40-38, TW123456,T0.02.
PSU Series User Manual 12 13 14 15 16 For further details, please see the programming manual, available on the GW Instek web site @ www.gwinstek.com. Note UART Remote Interface Configure UART The PSU uses the IN & OUT ports for UART communication coupled with RS232 (GW Part number PSU-232) or RS485 adapters (GW part number PSU-485) Overview The pin outs for the adapters are shown below. PSU-232 RS232 cable with DB9 connector 164 DB-9 Connector Remote IN Port Pin No. Pin No.
COMMUNICATION INTERFACE PSU-485 RS485 cable with DB9 connector Steps DB-9 Connector Remote IN Port Pin No. Pin No. Name Remarks Name Housing Shield Housing Shield 9 TXD - 6 RXD - 8 TXD + 3 RXD + 1 SG 1 SG 5 RXD - 5 TXD - 4 RXD + 4 TXD + 1. Connect the RS232 serial cable (included in the PSU-232 kit) or RS485 serial cable (included in the PSU-485 kit) to the (Remote IN port) on the rear panel.
PSU Series User Manual UART address if TDK is selected for F-75. F-76 = 00~31 3. The RMT indicator will turn on when a remote connection has been established. CV CC V A VOLTAGE VSR LAN RMT CURRENT ERR DLY ALM ISR M1 M2 M3 RUN RMT indicator Note 166 If TDK (emulation mode) is selected for F-75, the TDK GENESYS legacy commands should be used for remote commands. See the TDK Genesys user manual for details.
COMMUNICATION INTERFACE UART Function Check Functionality check Invoke a terminal application such as Realterm. To check the COM port No, see the Device Manager in the PC. For WinXP; Control panel → System → Hardware tab. Run this query command via the terminal application after the instrument has been configured for either RS232 or RS485 remote control (page 164). *idn? This should return the Manufacturer, Model number, Serial number, and Firmware version in the following format: GW-INSTEK,PSU40-38,,T0.
PSU Series User Manual Multiple Unit Connection Using Local RS485 Bus The PSU power supplies can have up to 31 units daisy-chained together using the 8 pin connectors (IN OUT ports) on the rear panel. The first unit in the chain is remotely connected to a PC using RS232 or RS485. Each subsequent unit is daisy-chained to the next using an RS485 local bus. The OUT port on the last terminal must be terminated by the end terminal connector.
COMMUNICATION INTERFACE 4. Terminate the OUT port of the last unit with the end terminal connector included in the PSU-232 or PSU-485 connection kit. 5. Press the Function key to enter the Page 109 Normal configuration settings for the master unit. Set the following settings: Configure the master unit as you normally would for RS232 or F-70 = 1 or 2 RS485 remote control, see page 164. Set the baud rate (set all units F-71 = 0~7 the same). See page 164. F-72 = 1 Set to 8 data bits. F-73 = 0 Parity to none.
PSU Series User Manual F-76 = 00~31 Set the address of each slave to a unique address identifier 7. Multiple units can now be operated at the same time. See the programming manual or see the function check below for usage details. Serial link cable with RJ-45 shielded connectors from PSU-232 or PSU485 connection kit 8 Pin Connector (IN) 8 Pin Connector (OUT) Pin No. Name Pin No.
COMMUNICATION INTERFACE Run this query command via the terminal application after the instruments have been configured for multi-unit control. See page 168. ADR 8 IDN? The identity string for the Master unit will be returned: GW-INSTEK,PSU40-38,,T0.01.12345678 Type the following: ADR 11 IDN? The identity string for the slave with address 11 will be returned: GW-INSTEK,PSU40-38,,T0.01.12345678 Note: TDK commands do not use LF (line feed) codes to terminate commands.
PSU Series User Manual Configure Ethernet Connection The Ethernet interface can be configured for a number of different applications. Ethernet can be configured for basic remote control or monitoring using a web server or it can be configured as a socket server. The PSU series supports both DHCP connections so the instrument can be automatically connected to an existing network or alternatively, network settings can be manually configured.
COMMUNICATION INTERFACE 2. Press the Function key to enter the Page 109 Normal configuration settings. Set the following LAN settings: F-36 = 1 Turn LAN on F-37 = 1 Enable DHCP F-59 = 1 Turn the web server on F-60 = 0 or 1 Set to 0 to disable web password, set to 1 to enable web password F-61 = 0000 Set the web password ~9999 3. The LAN indicator will turn on when a network cable is plugged in.
PSU Series User Manual F-42 = DDD IP Address part 4 of 4 http:// AAA.BBB.CCC.DDD The web browser interface appears. The web browser interface allows you to access the following: Network configuration settings Analog control pinouts & usage PSU dimensions Operating area diagram Note 174 For further details, please see the programming manual, available on the GW Instek web site @ www.gwinstek.com.
COMMUNICATION INTERFACE Sockets Server Configuration Configuration This configuration example will configure the PSU socket server. The following configuration settings will manually assign the PSU an IP address and enable the socket server. The socket server port number is fixed at 2268. 1. Connect an Ethernet cable from the network to the rear panel Ethernet port. LAN 2. Press the Function key to enter the Page 109 Normal configuration settings.
PSU Series User Manual Socket Server Function Check Background To test the socket server functionality, National Instruments Measurement and Automation Explorer can be used. This program is available on the NI website, www.ni.com., via a search for the VISA Run-time Engine page, or “downloads” at the following URL, http://www.ni.com/visa/ Requirements Operating System: Windows XP, 7, 8 Functionality check 1. Start the NI Measurement and Automation Explorer (MAX) program.
COMMUNICATION INTERFACE 3 2 4. Select Manual Entry of Raw Socket from the popup window. 4 5. Enter the IP address and the port number of the PSU. The port number is fixed at 2268. 6. Click the Validate button. 7. A popup will appear if a connection is successfully established. 8. Click Next.
PSU Series User Manual 7 5 6 8 9. Next configure the Alias (name) of the PSU connection. In this example the Alias is: PSU_DC1 10. Click finish. 9 10 11. The IP address of the PSU will now appear under Network Devices in the configuration panel. Select this icon now. 12. Click Open VISA Test Panel.
COMMUNICATION INTERFACE 12 11 13. Click the Configuration icon, 14. Click on I/O Settings. 15. Make sure the Enable Termination Character check box is checked, and the terminal character is \n (Value: xA). 16. Click Apply Changes. 13 14 15 16 17. Click the Input/Output icon. 18. Enter *IDN? in the Select or Enter Command dialog box if it is not already. 19. Click the Query button.
PSU Series User Manual 20. The *IDN? query will return the Manufacturer, model name, serial number and firmware version in the dialog box. GW-INSTEK,PSU40-38,TW123456,T0.02.20131205 17 18 19 20 Note 180 For further details, please see the programming manual, available on the GW Instek web site @ www.gwinstek.com.
FAQ FAQ • How often should the power supply be calibrated? • The OVP voltage is triggered earlier than expected. • Can I combine more than 1 cable together for the output wiring? • The accuracy does not match the specification. How often should the power supply be calibrated? The PSU should be calibrated by an authorized service center at least every 2 years. For details regarding calibration, see your local dealer or GWInstek at www.gwinstek.com / marketing@goodwill.com.tw.
PSU Series User Manual The accuracy does not match the specification. Make sure the device is powered On for at least 30 minutes, within +20°C~+30°C. This is necessary to stabilize the unit to match the specification. For more information, contact your local dealer or GWInstek at www.gwinstek.com / marketing@goodwill.com.tw.
APPENDIX APPENDIX PSU Factory Default Settings The following default settings are the factory configuration settings for the power supply. For details on how to return to the factory default settings, see page 47.
PSU Series User Manual Auto Calibration Parallel Control Measurement Average Setting Alarm Recovery and Output Status Lock Mode Setup Rear USB Speed GPIB address GPIB Enable/Disable SCPI Emulation LAN setting LAN Enable DHCP Power On Configuration Socket Server Enable/Disable Web Server Enable/Disable Web Password Enable/Disable UART Mode UART Baudrate UART Data Bits UART Parity UART Stop Bit UART TCP UART Address (For TDK) CV Control CC Control Output Status when Power ON Master/Slave Configuration Externa
APPENDIX Error Messages & Messages The following error messages or messages may appear on the PSU screen during operation.
PSU Series User Manual LED ASCII Table Character Set Use the following table to read the LED display messages.
APPENDIX PSU Specifications The specifications apply when the PSU is powered on for at least 30 minutes. Output Model PSU 6-200 12.5-120 20-76 40-38 60-25 Rated Output Voltage (*1) Rated Output Current (*2) Rated Output Power V 6 12.5 20 40 60 A 200 120 76 38 25 W 1200 1500 1520 1520 1500 Constant Voltage Mode Model PSU 6-200 12.5-120 20-76 40-38 60-25 Line regulation (*3) Load regulation (*4) Ripple and p-p (*6) noise (*5) r.m.s.
PSU Series User Manual Constant Current Mode Model PSU 6-200 12.5-120 20-76 40-38 60-25 Line regulation (*3) Load regulation (*11) Ripple and r.m.s. noise (*12) Temperature coefficient mA 22 14 9.6 5.8 4.5 mA 45 29 20.2 12.6 10 mA 400 240 152 95 75 ppm/ °C 100ppm/°C of rated output current, after a 30 minute warm-up.
APPENDIX Analog Programming and Monitoring Model External voltage control output voltage External voltage control output current External resistor control output voltage External resistor control output current Output voltage monitor Output current monitor Shutdown control Output on/off control Alarm clear control CV/CC/ALM/PWR ON/OUT ON indicator Trigger out Trigger in PSU 6-200 12.5-120 20-76 40-38 60-25 Accuracy and linearity: ±0.5% of rated output voltage.
PSU Series User Manual Front Panel Model PSU 6-200 12.5-120 20-76 40-38 60-25 mV mA Knobs 12 25 40 80 120 600 360 228 114 75 GREEN LED's: CV, CC, V, A, VSR, ISR, DLY, RMT, LAN, M1, M2, M3, RUN, Output ON RED LED's: ALM, ERR Lock/Local(Unlock), PROT(ALM_CLR), Function(M1), Test(M2), Set(M3), Shift, Output Voltage, Current USB port Type A USB connector Display, 4 digits Voltage accuracy Current accuracy 0.1% + 0.
APPENDIX Input Characteristics Model Norminal input rating Input voltage range Input frequency range Maximum input 100Vac current 200Vac Inrush current Maximum input power Power factor 100Vac 200Vac Efficiency (*13) 100Vac 200Vac Hold-up time PSU 6-200 12.5-120 20-76 40-38 60-25 100Vac to 240Vac, 50Hz to 60Hz, single phase 85Vac ~ 265Vac 47Hz ~ 63Hz A 21 A 11 Less than 50A. 2000 VA % % 0.99 0.
PSU Series User Manual Environment Conditions Model Weight Dimensions Cooling EMC Safety Withstand voltage Insulation resistance main unit only (W×H×D) PSU 6-200 kg Less than 8.7kg mm 3 12.5-120 20-76 40-38 60-25 423×43.6×447.2 Forced air cooling by internal fan. Complies with the European EMC directive 2004/108/EC for Class A test and measurement products. Complies with the European Low Voltage Directive 2006/95/EC and carries the CE-marking.
APPENDIX PSU Dimensions Current CV CC 0 - 40V / 0 - 38A V A VOLTAGE VSR LAN RMT CURRENT ERR DLY ALM ISR M1 Lock/Local PROT Function Test Set Unlock ALM_CLR M1 M2 M3 : Long Push M2 Shift M3 RUN Output 56.2 Voltage DC Power Supply 43.6 PSU 6-200, PSU 12.5-120, PSU 20-76, PSU 40-38, PSU 60-25 447.2 423.0 501.
PSU Series User Manual Declaration of Conformity We GOOD WILL INSTRUMENT CO., LTD. No. 7-1, Jhongsing Rd, Tucheng Dist., New Taipei City 236, Taiwan GOOD WILL INSTRUMENT (SUZHOU) CO., LTD. No. 69 Lushan Road, Suzhou New District Jiangsu, China. declare that the below mentioned product Type of Product: Programmable DC Power Supply Model Number: PSU 6-200, PSU 12.
INDEX INDEX Accessories ................................. 12 Alarm description ..................................... 27 Analog connector pin assignment ............................ 115 Analog control output control ............................. 128 overview ...................................... 113 remote monitoring ..................... 133 resistance control – current output ...................................... 125 resistance control – voltage output ......................................
PSU Series User Manual Marketing contact .......................................... 182 Messages ................................... 185 Model differences ...................... 10 OCP level .................................... 51 Operating area description ...... 22 Operation considerations ......... 29 floating output .............................. 32 inrush current ............................... 29 pulsed loads .................................. 29 reverse current ..............................