1. Power Supply
The DC resistance tester provides two types of power for testing: AC220V/DC12V. In the case of strong electromagnetic interference, it is recommended to use DC power for testing, as the test values are stable and the anti-power frequency interference capability is strong.
A. AC Power Supply Test of DC Resistance Tester:
Connect the AC220V power supply, the corresponding indicator light turns on, close the main power switch, the corresponding indicator light turns on, press the "Start/Stop" button to start testing. After the test is completed, turn off the main power switch (AC220V), the corresponding indicator light turns off, after discharging, switch the test clips and perform the test again.
B. Charging:
Connect the AC220V power supply, the charging indicator light turns on, indicating that the internal rechargeable battery is being charged. When the instrument is tested using AC power, it also charges the internal battery. (The instrument is designed with a charging protection circuit to prevent overcharging.)
C. DC Power Supply Test:
Close the main power switch (DC12V), the corresponding indicator light turns on, close the main power switch, the corresponding indicator light turns on, press the "Start/Stop" button to start testing. After the test is completed, turn off the main power switch (DC12V), the corresponding indicator light turns off, after discharging, switch the test clips and perform the test again.
2. Connection Method of Test Leads
Connect the I+, V+, V-, I- terminals of the instrument to the test object according to the method in Figure 1.
Connect them properly. This connection method can eliminate the contact resistance at A, B, C, D, and the influence of lead resistance on the measurement. The measured value is the resistance Rx between B and C (note: do not reverse B and C).
In use, if the test leads provided with the instrument are not long enough, you can extend them with wires of appropriate diameter.
3. Discharge
After the test is completed, you can directly turn off the main power. If testing inductive samples, do not disconnect the wires immediately after turning off the power; allow the instrument to continue discharging. Generally, discharge for at least 20 seconds, otherwise the back electromotive force of the inductor may endanger personal safety.
4. Measurement
When the DC resistance tester is turned on with the circuit not properly connected, the meter displays "E0000". Select the desired resistance range based on the value to be measured, press the corresponding range switch, the indicator light for that range turns on, and the four-and-a-half-digit LCD displays the stable value, which is the measured resistance value. Pay attention to the unit on the selected range when reading the value. When measuring large inductive samples such as power transformers, it is best to short-circuit other coils not being measured in the test circuit to avoid electromagnetic interference.
Main Features of DC Resistance Tester
1. Adopts high-speed 16-bit A/D converter, with stable measurement data and good repeatability.
2. Automatic program-controlled current source technology, with a total of 1000 current ranges set by the internal microcontroller automatically based on the measured resistance, achieving a wider measurement range and optimal measurement state without manual current range switching.
3. Fast response speed; during measurement, the tap changer can be switched directly, and the instrument will automatically prompt, and the new resistance value will be displayed quickly.
4. Highly intelligent design with clever and advanced function settings, capable of automatically detecting faults such as loose test leads or broken wires.
