User Manual PS280 & PS283 DC Power Supplies 070-8355-03
Copyright Tektronix, Inc. 1991. All rights reserved. Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes that in all previously published material. Specifications and price change privileges reserved. Tektronix, Inc., P.O. Box 1000, Wilsonville, OR 97070–1000 TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.
WARRANTY Tektronix warrants that this product will be free from defects in materials and workmanship for a period of one (1) year from the date of shipment. If any such product proves defective during this warranty period, Tektronix, at its option, either will repair the defective product without charge for parts and labor, or will provide a replacement in exchange for the defective product.
Table of Contents General Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii Getting Started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preparing the Power Supply for Use . . . . . . . . . . . . . . . . . . . . . Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Turning On the Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 4 8 Reference . . . . . . . . . . . . . . . . . . . . . . .
Table of Contents List of Figures Figure 1: Line Voltage Selectors, Power Input, and Fuse Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 2: PS280 or PS283 Front Panel . . . . . . . . . . . . . . . . . . . Figure 3: Constant Voltage/Constant Current Crossover . . . . . . Figure 4: Independent Floating Application . . . . . . . . . . . . . . . Figure 5: Independent Common Ground-Referenced Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Safety Summary Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it. Injury Precautions Use Proper Power Cord To avoid fire hazard, use only the power cord specified for this product. Avoid Electric Overload To avoid electric shock or fire hazard, do not apply a voltage to a terminal that is outside the range specified for that terminal.
General Safety Summary Do Not Operate in Wet/Damp Conditions To avoid electric shock, do not operate this product in wet or damp conditions. Do Not Operate in Explosive Atmosphere To avoid injury or fire hazard, do not operate this product in an explosive atmosphere. Product Damage Precautions Use Proper Voltage Setting Before applying power, ensure that the line selector is in the proper position for the power source being used.
General Safety Summary CAUTION. Caution statements identify conditions or practices that could result in damage to this product or other property. Terms on the Product These terms may appear on the product: DANGER indicates an injury hazard immediately accessible as you read the marking. WARNING indicates an injury hazard not immediately accessible as you read the marking. CAUTION indicates a hazard to property including the product.
General Safety Summary vi PS280 & PS283 User Manual
Getting Started The Tektronix PS280 or PS283 Laboratory DC Power Supply is a multifunction bench or portable instrument. This regulated power supply provides a fixed 5 V output for powering logic circuits and two variable outputs for a wide variety of test and experimental uses. The PS280 or PS283 contains two identical, independently adjustable DC power supplies that you can vary from 0 to 30 V. The current on the PS280 variable power supplies varies from 0 to 2 A.
Getting Started Preparing the Power Supply for Use Check the following items prior to operating the Laboratory DC Power Supply for the first time (see Figure 1 for locations of items 1 through 3): 1 3 2 Figure 1: Line Voltage Selectors, Power Input, and Fuse Locations CAUTION. To prevent damage to the instrument, set the line voltage selectors to the proper voltage setting and install the correct line voltage fuse before operating the equipment. 1.
Getting Started occurs. Refer to Appendix C: Replaceable Parts on page 33 for fuse part numbers. WARNING. To prevent electrical shock, connect the power cord to a properly grounded power source. The outside (ground) of this connector is connected through the equipment to the power source ground. Do not remove the ground lug from the power cord for any reason. 3. Connect the input power cord. Use only the power cords specified for this equipment.
Getting Started Front Panel Figure 2 shows the front-panel controls, connectors, and indicators with brief descriptions following the figure. 9 10 1 2 11 12 13 14 3 4 15 5 6 7 16 17 18 19 8 20 21 22 Figure 2: PS280 or PS283 Front Panel 1. LED Display. Lights when the instrument is turned on. The numbers indicate the voltage or current produced by the left variable power supply. 2. AMPS/VOLTS Switch.
Getting Started 3. AMPS Indicator. Lights when AMPS is selected with the AMPS/VOLTS switch for the left variable power supply. 4. VOLTS Indicator. Lights when VOLTS is selected with AMPS/VOLTS switch for the left variable power supply. 5. AMPS Indicator. Lights when AMPS is selected with the AMPS/VOLTS switch for the right variable power supply. 6. VOLTS Indicator. Lights when VOLTS is selected with AMPS/VOLTS switch for the right variable power supply. 7. AMPS/VOLTS Switch.
Getting Started 13. Output Terminals. These terminals for the left, variable power supply allow you to plug in the test leads as follows: H The red terminal on the right is the positive polarity output terminal. It is indicated by a + sign above it. H The black terminal on the left is the negative polarity output terminal. It is indicated by a – sign above it. H The green terminal in the middle is the earth and chassis ground. 14. VOLTAGE Knob.
Getting Started 17. Output Terminals. These terminals for the right, variable power supply allow you to plug in the test leads as follows: H The red terminal on the right is the positive polarity output terminal. It is indicated by a plus (+) sign above it. H The black terminal on the left is the negative polarity output terminal. It is indicated by a minus (–) sign above it. H The green terminal in the middle is the earth and chassis ground. 18. C.C. Indicator.
Getting Started Turning On the Instrument After you have ensured that the PS280 or PS283 is set up for the proper line voltage and has the proper fuse (refer to Preparing the Power Supply for Use on page 2), you are ready to turn it on. CAUTION. To avoid damaging the PS280 or PS283, do not use it when the ambient air temperature exceeds 40° C. Also, allow adequate space at the rear of the instrument to permit the heat sink to radiate heat. 1.
Reference This section tells how to set the PS280 or PS283 current limit. It also explains the constant voltage/constant current crossover characteristic of the instrument. Finally, the section includes procedures for using the instrument in both independent and tracking modes and provides examples of a variety of applications. Constant Voltage/Constant Current Crossover The PS280 or PS283 DC Power Supply features a constant voltage/constant current automatic crossover.
Reference VO Maximum Constant Current Range Crossover Point Output Voltage Constant Voltage Range Output Current IO Maximum Figure 3: Constant Voltage/Constant Current Crossover Setting the Current Limit Before you begin using the PS280 or PS283 to power a device, you should set its current limit lower than the maximum safe current for the device to be powered. CAUTION.
Reference 3. Rotate the VOLTAGE knob away from zero sufficiently to light the C.C. indicator. 4. Set the meter selection switch to AMPS so that the LED display shows the current. 5. Adjust the CURRENT knob for the desired current limit. 6. Read the value shown on the LED display. This is your preset current limit. Do not increase the current control setting. 7. Remove the short between the positive and negative output terminals. You are now ready to power your device.
Reference In stacked mode, you connect the negative output terminal of one variable power supply to the positive output terminal of the other. The stacked configuration allows you to test a circuit requiring between 30 and 60 V. A stacked configuration can be either floating or ground-referenced. Floating. In the independently floating mode, each variable power supply provides from 0 to 30 V at 0 to 2 A (0 to 1 A for the PS283). Figure 4 shows each of the three power supplies connected to a separate load.
Reference 4. Plug one of the test leads into the positive output terminal. 5. Plug the other test lead into the negative output terminal. 6. Press POWER to turn off the PS280 or PS283. 7. Clip the positive test lead to the positive pole of your device. 8. Clip the negative test lead to the negative pole of your device. 9. Press POWER to turn on the PS280 or PS283. 10. Push the AMPS/VOLTS selection switch so that the LED display shows either voltage or current, as you want. 11.
Reference SLAVE GND Load 3 –5 TO +25 V 0 to 2 A (PS280) 0 to 1 A (PS283) MASTER GND 5V FIXED 3A Load 2 –5 TO +25 V 0 to 2 A (PS280) 0 to 1 A (PS283) Load 1 –5 V 3A Figure 5: Independent Common Ground-Referenced Application In this configuration, each of the variable power supplies can be varied from –5 V to +25 V (+30 V overall). The GND post becomes the relative negative terminal for both variable outputs.
Reference 4. Set both variable supply CURRENT controls to midrange. 5. Set the AMPS/VOLTS switches for both power supplies to display volts. 6. Turn on the POWER to the PS280 or PS283. The display should read 0 V for both variable power supplies. An external meter connected across the load or load terminals should read –5 V. 7. Turn the POWER off to the PS280 or PS283 again. 8. Connect the device or devices to be tested. 9. Turn on the POWER to the PS280 or PS283 again. Adjust the voltages as needed.
Reference To test a circuit in a independent ground-referenced split application mode, follow these steps: 1. Turn the POWER off to the PS280 or PS283. 2. Connect the outputs as shown in Figure 6. 3. Set both variable supply VOLTAGE controls to the minimum setting. 4. Set both variable supply CURRENT controls to midrange. 5. Turn on the POWER to the PS280 or PS283. 6. Set the desired voltages for both variable power supplies. 7. Turn the POWER off to the PS280 or PS283 again. 8.
Reference Figure 8 shows the configuration for three ground-referenced positive power supplies. SLAVE GND MASTER Load 3 0 to 30 V 0 to 2 A (PS280) 0 to 1 A (PS283) GND Load 2 0 to 30 V 0 to 2 A (PS280) 0 to 1 A (PS283) 5V FIXED 3A Load 1 5V 0 to 3 A Figure 8: Three Ground-Referenced Positive Power Supplies Stacked. In the independently stacked mode, the variable power supplies are connected and provide from 0 to 60 V at 0 to 2 A (0 to 1 A for the PS283).
Reference SLAVE GND MASTER GND 5V FIXED 3A Load 2 Load 1 0 to +60 V –5 V Figure 9: Independent Positive Stacked Application To test a circuit in the independently stacked mode, follow these steps: 1. Turn the POWER off to the PS280 or PS283. 2. Connect the outputs as shown in Figure 9. 3. Set both variable supply VOLTAGE controls to the minimum setting. 4. Set both variable supply CURRENT controls to midrange. 5. Turn on the POWER to the PS280 or PS283. 6. Set the desired voltage.
Reference Figure 10 shows a stacked application in which you have a 0 to –60 V output from the variable power supplies and a +5 V output from the FIXED power supply.
Reference Tracking Modes There are two tracking modes in which you can operate the PS280 or PS283: series and parallel. Series. In series mode, the positive output terminal of the master variable power supply is internally connected to the negative output terminal of the slave power supply. This connection allows the PS280 or PS283 to produce 0 to 60 V at 0 to 2 A (0 to 1 A for the PS283).
Reference 1. Turn the POWER off to the PS280 or PS283. 2. Connect the outputs as shown in Figure 12. INTERNAL SLAVE GND MASTER GND 5V FIXED 3A Load 1 0 to +60 V Figure 12: Series Tracking Application 3. Set the PS280 or PS283 to series tracking mode by pressing the left TRACKING button. Make sure that the right TRACKING button is released (out). 4. Set the master AMPS/VOLTS switch to the voltage metering position. Set the slave AMPS/VOLTS switch to the current metering position.
Reference NOTE. In series tracking mode, the current flowing through the two supplies must be equal. Therefore, the maximum current limit is the lower of the values set by the two current control knobs. 7. Turn on the POWER to the PS280 or PS283. 8. Adjust the output voltage to the desired level using the master VOLTAGE knob. 9. Turn the POWER off to the PS280 or PS283 again. 10. Connect the device or devices to be tested. 11. Turn on the POWER to the PS280 or PS283 again.
Reference MASTER SLAVE Figure 13: Parallel Tracking Inside the PS280 or PS283 To test a circuit in the parallel tracking mode, follow these steps: 1. Turn the POWER off to the PS280 or PS283. 2. Connect the outputs as shown in Figure 14 on page 24. 3. Set the PS280 or PS283 to parallel tracking mode by pressing both tracking buttons. 4. Set the master AMPS/VOLTS switch to the voltage metering position, and set the slave AMPS/VOLTS switch to the current metering position.
Reference INTERNAL SLAVE GND MASTER GND 5V FIXED 3A Load 1 0 to +30 V 0 to 4 A (PS280) 0 to 2 A (PS283) Figure 14: Parallel Tracking Application 7. Adjust the output voltage to the desired level using the master VOLTAGE knob. 8. Turn the POWER off to the PS280 or PS283 again. 9. Connect the positive polarity of the device being powered to the positive master terminal. 10. Connect the negative polarity of the device being powered to the negative master terminal. CAUTION.
Appendix A: Specifications Table 1: Physical Characteristics Dimension Measurement Width 255 mm (10.0 in) Height 145 mm (5.7 in) Depth 335 mm (13.2 in) Weight 11.5 kg (25.4 lb) PS280 9.0 kg (19.9 lb) PS283 Table 2: Environmental Characteristics Characteristic Temperature Relative Humidity Storage –10_C to +70_C 70% Operating 0_C to 40_C 80% Table 3: Operational Characteristics Characteristic Measurement Outputs Two 0 to 30 VDC, one 5 VDC Voltage (5 V) 5.0 ±0.25 VDC at 3.
Appendix A: Specifications Table 3: Operational Characteristics (Cont.) Characteristic Measurement Line Regulation (CC) 0.2% +3 mA Load Regulation (5 V) 0.2% Load Regulation (CV) 0.01% +3 mV (rating current 3 A) 0.01% +5 mV (rating current >3 A) 300 mV (0–60 V single series tracking supply) Load Regulation (CC) 0.
Appendix A: Specifications Table 4: Electrical Characteristics Characteristic Measurement Line voltage 90 to 110 108 to 132 198 to 242 216 to 250, all VAC at 50–60 Hz Power consumption 386 VA, 300 W maximum (PS280) 265 VA, 200 W maximum (PS283) Table 5: Certifications and Compliances EC Declaration of Conformity – EMC Meets intent of Directive 89/336/EEC for Electromagnetic Compatibility.
Appendix A: Specifications 28 PS280 & PS283 User Manual
Appendix B: Maintenance This appendix provides information for the basic maintenance of the PS280 or PS283 Laboratory DC Power Supply. Cleaning To clean the Laboratory DC Power Supply, use a soft cloth dampened in a solution of mild detergent and water. Do not spray cleaner directly onto the instrument, since it may leak into the cabinet and cause damage. Do not use chemicals containing benzine, benzene, toluene, xylene, acetone, or similar solvents.
Appendix B: Maintenance Troubleshooting Electronic maintenance on the power supply must be performed by a trained technician. However, an operator can perform some basic and routine maintenance. Perform the following steps to isolate the fault: 1. The power switch is on. The instrument is plugged in. Neither the C.C. nor the C.V. indicator is lighted. Check the output terminals with a voltmeter. a. Set the voltage control of the voltmeter to midrange. b.
Appendix B: Maintenance 5. Verify that the line settings on the rear panel match the line voltage. Do they? Yes Go to step 7. No Go to step 6. 6. Reset the line settings. Refer to Preparing the Power Supply for Use on page 2. 7. Check the power cord. WARNING. To prevent personal injury, be sure the power cord is disconnected at both ends before you check it. Is the power cord frayed or broken? Yes Go to step 8. No Go to step 2. 8. Replace the power cord. 9. The power switch is on.
Appendix B: Maintenance 32 PS280 & PS283 User Manual
Appendix C: Replaceable Parts Replaceable parts may be ordered directly from your authorized Tektronix dealer. Standard Accessories The following items are shipped with the Laboratory DC Power Supply: Table 6: Standard Accessories Accessory Tektronix Part Number Fuse, 5 x 20 mm, 4 A, 250 V, SB (PS280: 90 – 132 V operation) 159-0297-00 Fuse, 5 x 20 mm, 2.
Appendix C: Replaceable Parts The following power cords are available: Table 8: Accessory Power Cords Plug Configuration 34 Normal Usage Tektronix Part Number North America 115 V 161-0104-00 Europe 230 V 161-0104-06 United Kingdom 230 V 161-0104-07 Australia 230 V 161-0104-05 North America 230 V 161-0104-08 Switzerland 230 V 161-0167-00 PS280 & PS283 User Manual
