Loop resistance tester will inevitably encounter various abnormal problems in our daily use. Let's talk about how to solve these abnormal problems.
1、 Phenomenon: ZC-302 loop resistance tester is connected to AC 220V AC power supply, the fan has no running sound, and press the "test switch", and the ammeter and micro ohmmeter have no display.
Cause: 220V AC power supply is blocked, and the fuse is not installed or fused.
Troubleshooting: check and eliminate. (the fuse of 100A instrument shall not be less than 6A. If it is fused again, contact the manufacturer for solution. (never connect DC or 380V AC power supply)
2、 Phenomenon: press the "test switch" of the loop resistance tester, the ammeter displays no current, and the * bit of the micro ohmmeter displays "1".
Cause: 100A current circuit is not connected properly. The tested switch is not closed.
Troubleshooting: check the test line, re connect and re clamp. Close the switch.
3、 Phenomenon: the test current of the loop resistance tester is normal, and the micro ohm value * bit displays "1"
Cause: wrong position of voltage clamp. The measured circuit resistance value exceeds 2000 μ Ω。 The voltage signal line is disconnected or not connected.
Troubleshooting: process the voltage signal circuit, clamp the voltage clamp. In case of over range: use a multimeter to measure the voltage values of P1 and P2, and the resistance value = voltage value / current value.
4、 Phenomenon: the output current of the loop resistance tester is dozens of times, less than 100A.
Cause: the power supply voltage is too low, the internal resistance of the power line is large or the contact is poor, and the voltage drop is too large when there is DC output, which can not reach 190V. C1 and C2 terminals are loose. Poor contact between the tested circuit and the test clamp.
Troubleshooting: use qualified power supply and use too long and too thin power cord to deal with the tested circuit and eliminate poor contact. Use proper force when twisting C1, C2, P1 and P2 terminals. (the test current is 30a, and the test value is credible)
When encountering the above similar problems, we can solve them according to this method. Zc-302 loop resistance tester may appear in general, that is, these reasons. I hope the above explanation will be helpful to you.
