Model UT39A/B/C: OPERATING MANUAL TABLE OF CONTENTS TITLE PAGE Overview 3 Unpacking Inspection 3 Safety Information 4 Rules For Safe Operation 5 International Electrical Symbols 7 The Meter Structure 7 Functional Buttons 8 Display Symbols 8 Measurement Operation 9 A. DC Voltage Measurement 9 B. AC Voltage Measurement 10 C. DC Current Measurement 11 D. AC Current Measurement 13 E. Measuring Resistance 14 F. Frequency Measurement (The Model UT39C only) 15 G.
Model UT39A/B/C: OPERATING MANUAL PAGE I. Diodes and Continuity Test J. Transistor Test Maintenance A. General Service B. Replacing the Battery C.
Model UT39A/B/C: OPERATING MANUAL Overview Warning To avoid electric shock or personal injury, read the “Safety Information” and “Rules for Safety Operation” carefully before using the Meter. Digital Multimeters Model UT39A, UT39B and UT39C (hereafter referred to as “the Meter”) are 3 1/2 digits with steady operations, fashionable structure and highly reliable hand-held measuring instrument.
Model UT39A/B/C: OPERATING MANUAL Safety Information This Meter complies with the standards IEC61010: in pollution degree 2, overvoltage category (CAT. I 1000V, CAT. II 600V) and double insulation. CAT. I: Signal level, special equipment or parts of equipment, telecommunication, electronic, etc., with smaller transient overvoltages than overvoltages CAT. II. CAT. II: Local level, appliance, PORTABLE EQUIPMENT etc., with smaller transient voltage overvoltages than CAT.
Model UT39A/B/C: OPERATING MANUAL Rules For Safe Operation 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 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. l Inspect the test leads for damaged insulation or exposed metal.
Model UT39A/B/C: OPERATING MANUAL 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. l Remove test leads and temperature probe from the Meter and turn the Meter power off before opening the Meter case.
Model UT39A/B/C: OPERATING MANUAL International Electrical Symbols Deficiency of Built-In Battery AC (Alternating Current) AC or DC Double Insulated Warning. Refer to the Operating Manual Conforms to Standards of European Union Grounding DC (Direct Current) Diode Continuity Test Fuse The Meter Structure (see figure 1) 1. LCD Display 2. Data Hold Button 3. Transistor Jack 4. COM Input Terminal 5. Other Input Terminals 6. mA Input Terminal 7. 20A/10A Input Terminal 8. Capacitance Jack 9. Rotary Switch 10.
Model UT39A/B/C: OPERATING MANUAL Functional Buttons Below table indicated for information about the functional button operations Button Operation Performed POWER Turn the Meter on and off. (Yellow Button) l Press down the POWER to turn on the Meter. l Press up the POWER to turn off the Meter. l Press HOLD once to enter hold mode. (Blue Button) l Press HOLD again to exit hold mode. l In Hold mode, is displayed and the HOLD present value is shown.
Model UT39A/B/C: OPERATING MANUAL Measurement Operation 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 UT39A/B/C: OPERATING MANUAL 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. 10MΩ.This loading effect can cause measurement errors in high impedance circuits.
Model UT39A/B/C: OPERATING MANUAL Note l If the value of voltage to be measured is unknown, use the maximum measurement position (750V) 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. 10MΩ. This loading effect can cause measurement errors in high impedance circuits.
Model UT39A/B/C: OPERATING MANUAL To measure current, do the following: 1. Turn off power to the circuit. Discharge all high-voltage capacitors. 2. Insert the red test lead into the mA or 20A or 10A terminal and the black test lead into the COM terminal. When measuring current at 200mA below, insert the red test lead into mA terminal while measuring current 200mA or above, insert the red test lead into 10A or 20A terminal 3. Set the rotary switch to an appropriate measurement position in A range. 4.
Model UT39A/B/C: OPERATING MANUAL D. AC Current Measurement (see figure 4 with dotted line) Warning Never attempt an in-circuit current measurement where the voltage between terminals and ground is greater than 60V or 30V rms If the fuse burns out during measurement, the Meter may be damaged or the operator himself may be hurt. Disconnect power supply before making measurement. Use proper terminals, function, and range for the measurement.
Model UT39A/B/C: OPERATING MANUAL l UT39C – At 20A Range: For continuous measurement 10 seconds and interval not less than 15 minutes l When current measurement has been completed, disconnect the connection between the testing leads and the circuit under test. E. Measuring Resistance (see figure 5) Black Red ( figure 5) 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.
Model UT39A/B/C: OPERATING MANUAL 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. The Model UT39C: Frequency Measurement (see figure 6) Black Red (figure 6) 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.
Model UT39A/B/C: OPERATING MANUAL G. The Model UT39C: Temperature Measurement (see figure 7) Black Red (see figure 7) 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. To measure temperature, connect the Meter as follows: 1. Insert the red temperature into the VΩ terminal and the black temperature probe into the COM terminal. 2. Set the rotary switch to 0C. 3.
Model UT39A/B/C: OPERATING MANUAL H. Capacitance Measurement (see figure 8) ( figure 8) Warning To avoid damage to the Meter or to the equipment under test, disconnect the tested circuit power when measuring on line capacitors and discharge all highvoltage capacitors before measuring capacitance. Use the DC voltage function to confirm that the capacitor is discharged. Never attempt to input over 60V in DC or 3V rms in AC to avoid personal dangerous. To measure capacitance, connect the Meter as follows: 1.
Model UT39A/B/C: OPERATING MANUAL I. Measuring Diodes & Continuity Warning To avoid damage to the Meter or to the equipment under test, disconnect circuit power and discharge all high-voltage capacitors before measuring diodes and continuity. Never attempt to input over 60V in DC or 3V rms in AC to avoid personal dangerous. Testing Diodes Use the diode test to check diodes, transistors, and other semiconductor devices.
Model UT39A/B/C: OPERATING MANUAL Testing for Continuity To test for continuity, connect the Meter as below: 1. Insert the red test lead into VΩ terminal and the black test lead into the COM terminal. 2. Set the rotary switch to . 1. Connect the test leads across with the object being measured. 4. The buzzer sounds continuously if the resistance of a circuit under test is 10Ω, it indicates the circuit is in good connection.
Model UT39A/B/C: OPERATING MANUAL Note l When transistor measeurement has been completed, remove the transistor from the transistor jack. Sleep Mode To preserve battery life, the Meter automatically turns off if you do not turn the rotary switch or press any button for around 15 minutes. At that time, the Meter consumes around 10µA current. The Meter can be activated by pressing the POWER two times. General Specifications l Maximum voltage between any Terminals and Grounding: 1000V.
Model UT39A/B/C: OPERATING MANUAL Accuracy Specifications Accuracy: (a% reading + b digits), guarantee for 1 year. Operating temperature: 230C 50C. Relative humidity: <75%. Temperature coefficient: 0.1 x (specified accuracy) / 10C A. DC Voltage Range Resolution 200mV Accuracy Overload UT39A UT39B UT39C Protection 100µV 250V DC or AC rms. 2V 1mV 20V 10mV 1000V DC 200V 100mV or 750V AC. 1000V 1V (0.5%+1) (0.8%+2) Remark: l Input impedance: 10MΩ. B.
Model UT39A/B/C: OPERATING MANUAL C. DC Current Range Resolution 20µA 0.01µA 200µA 0.1µA 2mA 1µA 20mA 10µA 200mA 100µA Accuracy Overload UT39A UT39B UT39C Protection (2%+5) 0.315A. 250V (0.8%+3) (0.8%+1) (0.8%+1) fast type fuse, φ 5 x 20mm (1.5%+1) 10A/20A 10mA (2%+5) Un-Fused Remark: l UT39A/UT39B - At 10A Range: For continuous measurement 10 seconds and interval not less than 15 minutes.
Model UT39A/B/C: OPERATING MANUAL E. Resistance Test Range Resolution 200Ω 0.1Ω 2kΩ 1Ω 20kΩ 10Ω 200kΩ 100Ω 2MΩ 1kΩ 20MΩ 10kΩ 200MΩ 100kΩ Accuracy Overload UT39A UT39B UT39C Protection (0.8%+3) (0.8%+1) 250V DC or AC rms (0.8%+1) (0.8%+1) (1%+2) [5%(reading-10)+10] Remark: l Open circuit voltage: At 200MΩ range: approx. 3V Other ranges: 700mV l At 200MΩ range, test lead is in short circuit, and it is normal to display 10 digits.
H. Capacitance Range Resolution Accuracy Overload UT39A UT39B UT39C Protection 1pF (4%+3) 0.1nF 1nF 250V AC (4%+3) (4%+3) 10nF Remark: l Testing signal: approx. 400Hz, 40mV rms. I. Diodes and Continuity Test Function Range Resolution Diode Input Protection 1mV Continuity Buzzer 1 Remark Open circuit voltage approx.2.8V 250V DC or AC Approx. <70 buzzer beeps continuously J. Transistor Test Range Remarks Can measure NPN or PNP hFE transistor.
Model UT39A/B/C: OPERATING MANUAL Maintenance 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 UT39A/B/C: OPERATING MANUAL To replace battery: 1. 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. 2. Press the Meter power off 3. Remove the screw from the battery compartment, and then take out the battery door from the battery compartment. 4. Remove the battery from the battery compartment. 5. Replace the battery with a new 9V battery (NEDA 1604 or 6F22 or 006P). 6.
Model UT39A/B/C: OPERATING MANUAL 6. Remove the fuse by gently prying one end loose, and then take out the fuse from its bracket. 7. Install ONLY replacement fuses with the identical type and specification as follows and make sure the fuse is fixed firmly in the bracket. 0.315A. 250V fast type fuse, φ 5 x 20mm. 8. Rejoin the case bottom and the case top, and install the screw. 9. Rejoin the battery door from the battery compartment, and install the screw 10. Rejoin the holster and the Meter.
Model UT39A/B/C: OPERATING MANUAL C Copyright 2004 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.
