Model UT50A/B/C: OPERATING MANUAL Table of Contents Page Title Overview Unpacking Inspection Safety Information Rules For Safe Operation International Electrical Symbols The multimeter Structure Functional Buttons Display Symbols Measurement Operation A. DC Voltage Measurement B. AC Voltage Measurement C. DC Current Measurement D. AC Current Measurement E. Measuring Resistance F. The Model UT50C: Frequency Measurement G. The Model UT50B/UT50C: Temperature Measurement H. Capacitance Measurement I.
Model UT50A/B/C: OPERATING MANUAL Title E. F. G. H. I. Page Resistance Test The Model UT50C: Frequency The Model UT50B/UT50C: Temperature Capacitance Diodes and Continuity Test Maintenance A. B. C.
Model UT50A/B/C: OPERATING MANUAL Overview Warning To avoid electric shock or personal injury, read the "Safety Information" and "Rules for Safe Operation" carefully before using the Meter. Digital Multimeters Model UT50A, UT50B and UT50C (hereafter referred to as “the Meter”) are 3 1/2 digits with steady operations, fashionable structure and highly reliable hand-held measuring instrument.
Model UT50A/B/C: OPERATING MANUAL Unpacking Inspection Open the package case and take out the Meter. Check the following items carefully to see any missing or damaged part: Item 1 2 3 4 Description English Operating Manual Test Lead Test Clip Point Contact Temperature Probe (UT50B/UT50C only) Qty 1 piece 1 pair 1 pair 1 piece In the event you find any missing or damage, please contact your dealer immediately.
Model UT50A/B/C: OPERATING MANUAL Safety Information This Meter complies with the standards IEC61010: in pollution degree 2, overvoltage category (CAT. II 1000V, CAT. III 600V) and double insulation. CAT. II: Local level, appliance, PORTABLE EQUIPMENT etc., with smaller transient voltage overvoltages than CAT. III CAT. III: Distribution level, fixed installation, with smaller transient overvoltages than CAT.
Model UT50A/B/C: OPERATING MANUAL Rules For Safe Operation (1) Warning To avoid possible electric shock or personal injury, and to avoid possible damage to the Meter or to the equipment under test, adhere to the following rules: l l l l l l l l Before using the Meter inspect the case. Do not use the Meter if it is damaged or the case (or part of the case) is removed. Look for cracks or missing plastic. Pay attention to the insulation around the connectors.
Model UT50A/B/C: OPERATING MANUAL Rules For Safe Operation (2) l Disconnect circuit power and discharge all highvoltage capacitors before testing resistance, continuity, diodes, capacitance or current. l Before measuring current, check the Meter’s fuses and turn off power to the circuit before connecting the Meter to the circuit. l Replace the battery as soon as the battery indicator appears. With a low battery, the Meter might produce false readings that can lead to electric shock and personal injury.
Model UT50A/B/C: OPERATING MANUAL International Electrical Symbols AC (Alternating Current). DC (Direct Current). AC or DC. Grounding. Double Insulated. Deficiency of Built-In Battery. Continuity Test. Diode. Capacitance Test. Fuse. Warning. Refer to the Operating Manual. Conforms to Standards of European Union.
Model UT50A/B/C: OPERATING MANUAL The multimeter Structure (see figure 1) ( figure 1) LCD Display Data Hold Button.
Model UT50A/B/C: OPERATING MANUAL Functional Buttons Below table indicated for information about the functional button operations Button Operation Performed Turn the Meter on and off. POWER (Yellow Button) l Press down the POWER to turn on the Meter. l Press up the POWER to turn off the Meter. HOLD (Blue Button) l l l Press HOLD once to enter hold mode. Press HOLD again to exit hold mode. In Hold mode, is displayed and the present value is shown.
Model UT50A/B/C: OPERATING MANUAL Display Symbols (see figure 2) 10-14 ( figure 2) No. 1 2 3 4 5 6 7 8 9 10 11 Symbol Meaning Dangerous Voltages. The battery is low. Warning: To avoid false readings, which could lead to possible electric shock or personal injury, replace the battery as soon as the battery indicator appears. Indicator for AC voltage or current.The displayed value is the mean value. Indicates negative reading. Test of diode. Data hold is active. The continuity buzzer is on.
Model UT50A/B/C: OPERATING MANUAL Display Symbols (see figure 2) No. 12 13 14 Symbol nF, µF Meaning F: Farad. The unit of capacitance. µF: Microfarad.1 x 10-6 or 0.000001 farads. nF: Nanofarad. 1 x 10-9 or 0.000000001 farads. The unit of frequency in cycles/ kHz second. Kilohertz. 1 x 10-3 or 1,000 hertz. Ω: Ohm. The unit of resistance. Ω,kΩ,MΩ kΩ: kilohm. 1 x 103 or 1000 ohms. MΩ: Megaohm. 1 x 106 or 1,000,000 ohms.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(1) l Make sure the Sleep Mode is not on if you found there is no display on the LCD after turning on the Meter. l Make sure the Low Battery Display is not on, otherwise false readings may be provided. l Pay extra attention to the symbol which is located besides the input terminals of the Meter before carrying out measeurement. A.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(2) Note l If the value of voltage to be measured is unknown, use the maximum measurement position (1000V) and reduce the range step by step until a satisfactory reading is obtained. l The LCD displays “1” indicating the existing selected range is overloaded, it is required to select a higher range in order to obtain a correct reading. l In each range, the Meter has an input impedance of approx.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(3) The Model UT50A: The AC voltage measurement has 5 measurement positions on the rotary switch: 200mV, 2V, 20V, 200V and 750V The Model UT50B/UT50C: The AC voltage measurement has 4 measurement positions on the rotary switch: 2V, 20V, 200V and 750V To measure AC Voltage, connect the Meter as follows: 1. 2. 3. Insert the red test lead into the VΩ terminal and the black test lead into the COM terminal.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(4) C. DC Current Measurement (see figure 5) black red ( figure 5) Warning Never attempt an in-circuit current measurement where the open circuit voltage between terminals and ground is greater than 60V DC or 30V rms. If the fuse burns out during measurement, the Meter may be damaged or the operator himself may be hurt. Use proper terminals, function, and range for the measurement.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(5) 2. Insert the red test lead into the µAmA (The Model UT50B/UT50C) or 20A terminal and the black test lead into the COM terminal. 3. Set the rotary switch to an appropriate measurement position in A range. 4. Break the current path to be tested. Connect the red test lead to the more positive side of the break and the black test lead to the more negative side of the break. 5. Turn on power to the circuit. The measured value shows on the display.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(6) Warning Never attempt an in-circuit current measurement where the voltage between terminals and ground is greater than 60V. If the fuse burns out during measurement, the Meter may be damaged or the operator himself may be hurt. Use proper terminals, function, and range for the measurement. When the testing leads are connected to the current terminals, do not parallel them across any circuit.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(7) E. Measuring Resistance (see figure 7) red black ( figure 7) Warning To avoid damages to the Meter or to the devices under test, disconnect circuit power and discharge all the high-voltage capacitors before measuring resistance. The resistance ranges are: The Model UT50A/UT50B: 200Ω, 2kΩ, 20kΩ, 200kΩ, 2MΩ, 20MΩand 200MΩ. The Model UT50C: 200Ω, 2kΩ, 20kΩ, 200kΩ, 2MΩ and 200MΩ. To measure resistance, connect the Meter as follows: 1.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(8) measured resistance value (Y) – (X) = precision readings of resistance. l For high resistance (>1MΩ), it is normal taking several seconds to obtain a stable reading. l When there is no input, for example in open circuit condition, the Meter displays “1”. l When resistance measurement has been completed, disconnect the connection between the testing leads and the circuit under test. F.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(9) Note l When Hz measurement has been completed, disconnect the connection between the testing leads and the circuit under test. G. The Model UT50B/UT50C: Temperature Measurement (see figure 9) ( figure 9) Warning To avoid harm to you or damages to the Meter, do not attempt to measure voltages higher than 60V in DC or 30V rms in AC although readings may be obtained. o The temperature measurement range is from -40 C~ o o o 1000 C or -40 F~1832 F.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(10) l The included temperature probe can only be measured o up to 250 C For any mesaurement higher than that, the rod type temperature probe must be used instead. l When temperature measeuremnet has been completed, disconnect the connection between the testing leads and te circuit under test. H.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(11) Note l For testing the capacitor with polarity, connect the red test lead to anode & black test lead to cathode l When the tested capacitor is shorted or the capacitor value is overloaded, the LCD display “1”. l To minimize the measurement error caused by the distributed capacitor, the testing lead or testing clip should be as short as possible. When the tested capacitor is greater than 30 µF, reading is for reference only.
Model UT50A/B/C: OPERATING MANUAL Measurement Operation(12) Note l In a circuit, a good diode should still produce a forward voltage drop reading of 0.5V to 0.8V; however; the reverse voltage drop reading can vary depending on the resistance of other pathways between the probe tips. l Connect the test leads to the proper terminals as said above to avoid error display. The LCD will display “1” indicating open-circuit for wrong connection.
Model UT50A/B/C: OPERATING MANUAL Sleep Mode Turning on the Auto Display Backlight The Meter has a built-in sensor. Therefore the Display Backlight turns on and off automatically depending on the brightness of the environment. In a dim condition, the Display Backlight turns on automatically while in a bright condition, the Display Backlight turns off automatically.
Model UT50A/B/C: OPERATING MANUAL General Specifications l l l l l l l l l l l l l l l l l l Maximum voltage between any Terminals and Grounding : 1000V rms. Fused Protection for mA Input Terminal : 0.5A, 250V fast type, 5x20mm. Fused Protection for 20A Input Terminal : Un-fused. Range : Manual ranging. Maximum Display : Display :1999. Mesaurement Speed : Updates 2~3 times/second. o o Temperature : Operating: 0 C~40 C o o (32 F~104 F); o o o o Storage : -10 C~50 C( 14 F~122 F).
Model UT50A/B/C: OPERATING MANUAL Accuracy Specifications(1) Accuracy: (a% reading + b digits),guarantee for 1 year. o o Operating temperature:23 C 5 C. Relative humidity:<75%. o Temperature coefficient: 0.1 x (specified accuracy) / 1 C. A. DC Voltage Range Resolution 200mV 100µV 2V 20V 200V 1000V 1mV 10mV 100mV 1V Accuracy Overload UT50A UT50B UT50C Protection 250VDCor ACrms. (0.5%+1) 1000V DC or 750V AC rms. (0.8%+2) Remark: Input impedance: 10MΩ B.
Model UT50A/B/C: OPERATING MANUAL Accuracy Specifications(2) C. DC Current Range Resolution 20µA 0.01µA UT50A Accuracy UT50B (0.8%+1) 2mA 1µA 20mA 10µA 200mA 100µA 20A 10mA (0.8%+1) (1.5%+1) (2%+5) Overload UT50C Protection 0.5A. 250V fast type fuse, 5x20 (0.8%+1) mm Un-Fused Remarks: l At 20A Range: For continuous measurement 10 seconds and interval not less than 15 minutes. l Measurement voltage drop: Full range at 200mV. D. AC Current Range Resolution 200µA 2mA 20mA 200mA 20A 0.
Model UT50A/B/C: OPERATING MANUAL Accuracy Specifications(3) E. Resistance Test Range Resolution 200Ω 2kΩ 20kΩ 200kΩ 2MΩ 20MΩ 200MΩ 0.1Ω 1Ω 10Ω 100Ω 1kΩ 10kΩ 100kΩ Accuracy Overload UT50A UT50B UT50C Protection (0.8%+3) (0.8%+1) 250V DC or AC rms (1%+2) [5%(reading-10)+10] Remarks: l Open circuit voltage: 700mV (At 200MΩ range, it is approx. 2.8V) l At 200MΩ range , test lead is in short circuit , and it is normal to display 10 digits. During measurement, subtract the 10 digits from the reading. F.
Model UT50A/B/C: OPERATING MANUAL Accuracy Specifications(4) H. Capacitance Range Resolution 2nF 20nF 200nF 2µF 100µF 1pF 10pF 0.1nF 1nF 0.1µF Accuracy Overload UT50A UT50B UT50C Protection (4%+3) (4%+3) 250V AC (4%+3) (5%+4) Remarks:Testing signal:approx. 400Hz 40mV rms. When the tested capacitor is greater than 30 µF, reading is for reference only. I. Diodes and Continuity Test Range Resolution Input Protection 1mV 250V DC or AC 1Ω 30 Remark Open circuit voltage approx.2.
Model UT50A/B/C: OPERATING MANUAL Maintenance(1) This section provides basic maintenance information including battery and fuse replacement instruction. Warning Do not attempt to repair or service your Meter unless you are qualified to do so and have the relevant calibration, performance test, and service information. To avoid electrical shock or damage to the Meter, do not get water inside the case. A. General Service l Periodically wipe the case with damp cloth and mild detergent.
Model UT50A/B/C: OPERATING MANUAL Maintenance(2) Warning To avoid false readings, which could lead to possible electric shock or personal injury,replace the battery as soon as the battery indicator To replace battery: 1. 2. 3. 4. 5. 6. appears. Disconnect the connection between the testing leads and the circuit under test, and remove the testing leads away from the input terminals of the Meter.
Model UT50A/B/C: OPERATING MANUAL Maintenance(3) 1. Install ONLY replacement fuses with the identical type and specification as follows and make sure the fuse is fixed firmly in the bracket. 0.5A. 250V fast type fuse, φ 5x20mm. 2. Rejoin the case bottom and the case top, and install the screw and rubber feet Replacement of fuses is seldom required. Burning of a fuse always results from the improper operation. ~ END ~ This operating manual is subject to change without notice.
Model UT50A/B/C: OPERATING MANUAL Copyright 2001 Uni-Trend International Limited. All rights reserved. Manufacturer: UNI-TREND TECHNOLOGY(DONG GUAN)LIMITED Address: Dong Fang Da Dao, Bei Shan Dong Fang Industrial Development District, Hu Men Town, Dong Guan City, Guang Dong Province, China Headquarters: Uni-Trend International Limited Address: Rm901, 9/F, Nanyang Plaza 57 Hung To Road Kwun Tong Kowloon, Hong Kong Tel: (852) 2950 9168 Fax: (852) 2950 9303 Email: info@uni-trend.com http://www.uni-trend.
