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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 72-720 and 72-7725 (hereafter
referred to as “the Meter”) are 3 1/2 digits with steady
operations, fashionable structure and highly reliable
hand-held measuring instrument. The Meter uses large
scale of integrated circuit with double integrated A/D
converter as its core and has full range overload
protection. The Meter not only can measure AC/DC
Voltage, AC/DC Current, Resistance, Capacitance,
Temperature, Frequency, Diodes and Continuity, but also
has Data Hold, Full Icon Display and Sleep Mode features.

The Meter adopted advanced “co-injection” technique in
order to provide sufficient insulation and anti-shaking.
In addition, the Automatic Display Backlight feature
enables user to work in a dim condition.

Model 72-7720/72-7725: OPERATING MANUAL

 

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Содержание 72-772

Страница 1: ...ctional 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 Model 72 7725 Frequency Measurement G Model 72 7725 Temperature Measurement H Capacitance Measurement I Measuring Diodes Continuity General Specifications Testing for Continuity Sleep Mode Turning on the Auto Display Back...

Страница 2: ...ity Test 30 30 C Replacing the Fuses 31 32 32 32 Model 72 7720 72 7725 OPERATING MANUAL 2 Title E Resistance Test F Model 72 7725 Frequency G Model 72 7725 Temperature H Capacitance Maintenance A General Service B Replacing the Battery ...

Страница 3: ...es large scale of integrated circuit with double integrated A D converter as its core and has full range overload protection The Meter not only can measure AC DC Voltage AC DC Current Resistance Capacitance Temperature Frequency Diodes and Continuity but also has Data Hold Full Icon Display and Sleep Mode features The Meter adopted advanced co injection technique in order to provide sufficient ins...

Страница 4: ...for missing or damaged parts In the event you find items missing or damaged please contact your dealer immediately Model 72 7720 72 7725 OPERATING MANUAL 4 Item 1 2 3 4 Description English Operating Manual Test Lead Test Clip Point Contact Temperature Probe 72 7725 only Qty 1 piece 1 pair 1 pair 1 piece ...

Страница 5: ...h smaller transient overvoltages than CAT IV Use the Meter only as specified in this operating manual otherwise the protection provided by the Meter may be impaired In this manual a Warning identifies conditions and actions that pose hazards to the user or may damage the Meter or the equipment under test A Note identifies the information that user should pay attention to International electrical s...

Страница 6: ...ore using the Meter l Do not apply more than the rated voltage as marked on the Meter between the terminals or between any terminal and ground l The rotary switch should be placed in the correct position and no changeover of range shall be made during measurement to prevent damage of the Meter l When working at an effective voltage over 60V DC or 30V rms AC special care should be taken for there i...

Страница 7: ...ase l When servicing the Meter use only the same model number or identical electrical specifications replacement parts l The internal circuit of the Meter shall not be altered at will to avoid damage of the Meter and any accident l Soft cloth and mild detergent should be used to clean the surface of the Meter when servicing No abrasive and solvent should be used to prevent the surface of the Meter...

Страница 8: ...rent 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 8 Model 72 7720 72 7725 OPERATING MANUAL ...

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Страница 17: ...negative side of the break 5 Turn on power to the circuit The measured value shows on the display Measurement Operation 5 Note l If the value of current to be measured is unknown use the maximum measurement position 20A and 20A terminal and reduce the range step by step until a satisfactory reading is obtained l When current measurement has been completed disconnect the connection between the test...

Страница 18: ...t to be measured is unknown use the maximum measurement position 20A and 20A terminal and reduce the range step by step until a satisfactory reading is obtained l When current measurement has been completed disconnect the connection between the testing leads and the circuit under test To measure current do the following 1 Turn off power to the circuit Discharge all high voltage capacitors 2 Insert...

Страница 19: ...Ω terminal and the black test lead into the COM terminal 2 Set the rotary switch to an appropriate measurement position inΩ range 3 Connect the test leads across with the object being measured The measured value shows on the display Note l The test leads can add 0 1Ωto 0 3Ω of error to the resistance measurement To obtain precision readings in low resistance that is the range of 200Ω short circuit...

Страница 20: ...pt to measure voltages higher than 60V in DC or 30V rms in AC although readings may be obtained When the frequency signal to be tested is higher than 30V rms the Meter cannot guarantee accuracy of the measurement figure 8 red black The frequency measurement ranges are 2kHz and 20kHz To measure frequency connect the Meter as follows 1 Insert the red test lead into the VΩ terminal and the black test...

Страница 21: ... measurement range is from 40 o C 1000 o C or 40 o F 1832 o F To measure temperature connect the Meter as follows Note l The Meter automatically displays the temperature value inside the Meter when there is no temperature probe connected Measurement Operation 9 1 Insert the red temperature probe into the V Ω terminal and the black temperature probe into the COM terminal 2 Set the rotary switch to ...

Страница 22: ... measurement positions on the rotary switch 2nF 20nF 2µF and 100µF Model 72 7725 Capacitance measurement has four measurement positions on the rotary switch 20nF 200nF 2µF and 100µF To measure capacitance connect the Meter as follows 1 Insert the red test clip or red test lead into the VΩ terminal and the black test clip or black test lead into the µmA Model 72 7720 or mA Model 72 7725 terminal 2 ...

Страница 23: ...est disconnect circuit power and discharge all high voltage capacitors before measuring diodes and continuity Testing Diodes Use the diode test to check diodes transistors and other semiconductor devices The diode test sends a current through the semiconductor junction and then measures the voltage drop across the junction A good silicon junction drops between 0 5V and 0 8V To test out a diode out...

Страница 24: ...n completed disconnect the connection between the testing leads and the circuit under test 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 3 Connect the test leads across with the object being measured The buzzer sounds if the resistance of a circuit under t...

Страница 25: ...urning 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 Model 72 7720 72 7725 OPERATING MANUAL ...

Страница 26: ...ature Operating 0 o C 40 o C 32 o F 104 o F Storage 10 o C 50 o C 14 o F 122 o F l Relative Humidity 75 0 o C 30 o C 50 31 o C 40 o C l Altitude Operating 2000m Storage 10000m l Battery Type 9V NEDA1604 or 6F22 or 006P l Low Battery Display l Data Hold Display l Negative read Display l Overload Display 1 l Dimensions HxWxL 165x80x38 3mm l Weight Approx 275g battery included l Safety Compliances IE...

Страница 27: ... Remarks l Input impedance 10MΩ l Frequency response 40Hz 400Hz l Display effective value of sine wave mean value response 200mV 2V 20V 200V 1000V 100µV 1mV 10mV 100mV 1V Range Resolution 0 5 1 Overload Protection 72 7720 72 7725 Accuracy 250VDCor ACrms 0 8 2 1000V DC or 750VAC rms 100µV 1mV 10mV 100mV 1V Range Resolution 1 2 3 Overload Protection Accuracy 250V DC or AC rms 0 8 3 1 2 3 1000V DC or...

Страница 28: ...nutes l Measurement voltage drop Full range at 200mV D AC Current Range Resolution 1 3 Overload Protection 72 7720 72 7725 Accuracy 3 5 1 8 3 200µA 2mA 20mA 200mA 20A 0 1µA 1µA 10µA 100µA 10mA 1 3 0 5A 250V fast type fuse 5x20 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 l Frequency rea...

Страница 29: ... lead is in short circuit and it is normal to display 10 digits During measurement subtract the 10 digits from the reading F Model 72 7725 Frequency Remarks Input Sensitivity 200mV G The Model 72 7725 Temperature Range Resolution 3 3 Overload Protection Accuracy 250V AC 40 o C 0 o C 0 o C 400 o C 400 o C 1000 o C 40 o F 32 o F 32 o F 752 o F 752 o F 1832 o F 1 3 2 5 3 4 1 4 1 5 15 1 o C 1 o F 1Hz ...

Страница 30: ... 100µF 1pF 10pF 0 1nF 1nF 0 1µF 5 4 4 3 250V AC 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 1mV 1Ω Range Resolution Input Protection Remark Open circuit voltage approx 2 8V 250V DC or AC Model 72 7720 72 7725 OPERATING MANUAL ...

Страница 31: ...t water inside the case A General Service l Periodically wipe the case with damp cloth and mild detergent Do not use chemical solvent l To clean the terminals with cotton bar with detergent as dirt or moisture in the terminals can affect readings l Turn the Meter OFF when it is not in use and take out the battery when not using for a long time l Do not store the Meter in place of humidity high tem...

Страница 32: ...attery with a new 9V battery NEDA 1604 or 6F22 or 006P 6 Rejoin the battery compartment and the case bottom and install the screw and rubber feet C Replacing the Fuses Warning To avoid electrical shock arc blast personal injury or damage to the Meter use specified fuses ONLY in accordance with the following procedure To replace the Meter s fuse 1 Disconnect the connection between the test leads an...

Страница 33: ... 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 72 7720 72 7725 OPERATING MANUAL This operating manual is subject to change without notice ...

Страница 34: ...34 Tenma Test Equipment 405 S Pioneer Blvd Springboro Ohio 45066 www tenma com Model 72 7720 72 7725 OPERATING MANUAL ...

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