1. [Phenomena] Connect the 220V AC power supply, the fan has no running sound, and press the "test switch", the ammeter and micro-ohmmeter do not display. [Cause] The 220V AC power supply is blocked, and the fuse is not installed or blown. [Exclusion method] Check and exclude. (The 100A instrument insurance is not less than 6A and it will be blown again and the factory will solve it. (Do not connect to DC or 380V AC power)
2, [phenomenon] Press the "test switch", the ammeter shows no current, and the highest position of the micro-ohmmeter shows "1". [Cause] The 100A current loop is not connected properly. The switch being tested is not closed. [Remedy] Check the test lead, reconnect, and re-clamp. Close the switch.
3, [phenomenon] The test current is normal, and the highest micro-ohm value shows "1" [reason] The position of the voltage clamp is wrong. The resistance value of the circuit under test exceeds 2000. The voltage signal line is broken or not connected. [Remedy] Deal with the voltage signal loop, and clamp the voltage clamp. When the range is exceeded: use a multimeter to measure the voltage values of P1 and P2, resistance value = voltage value/current value.
4, [phenomenon] The output current is dozens of times, less than 100A. [Cause] The power supply voltage is too low, the internal resistance of the power cord is large or the contact is poor, and the voltage drop is too large when there is a DC output, which cannot reach 190V. The C1 and C2 terminals are loose. The circuit under test and the test clip are not in good contact. [Exclusion method] Use a qualified power supply, and use a power cord that is too long and too thin to deal with the circuit under test and eliminate poor contact. When twisting the C1, C2, P1, P2 terminals, the force should be appropriate. (The test current is reliable at the 30A test value)
5, [phenomenon] The test current is normal, and the micro-ohm value is abnormal and not repeated. [Cause] The contact of the voltage signal circuit is poor, and it is always on and off. The resistance of the measured resistance itself is not in good contact, and the resistance value changes. [Exclusion method] Ensure that the contact is good and reliable. Check and rule out.
6, [phenomenon] The test current is normal, and the micro-ohmmeter shows a negative value. [Cause] The voltage clamp is misplaced, and the positive and negative connections are reversed. [Exclusion method] Correction, should be: P1+, P2|.
7,[Phenomena] During the calibration test, sometimes the displayed value fluctuates greatly. [Cause] During the verification test, the test wire is in the shape of an inductive coil and is not spread out. [Remedy] Pull apart the test lead and reduce its inductance and mutual inductance.