In order to avoid false alarms, the residual current sensor must distinguish the phase line, N line and PE line in the power grid before wiring. Otherwise, problems will occur, resulting in inaccurate measurement data and false alarms. And the phase line and the N line must pass through the residual current sensor together, and the PE line cannot pass through the transformer, which also affects the deviation of the circuit parameters, and should be treated with caution.
If the N line does not pass through the residual current sensor together with the phase line, once the three-phase load is unbalanced, a current will flow through the N line, and the detector detects the current signal, causing a malfunction. If the PE line passes through the transformer together with the N line and the phase line, it will also cause an error alarm of the monitoring detector, which seriously affects the normal operation of its work.
The N lines between different circuits are not connected or grounded repeatedly. Otherwise, it will cause malfunction, and the leakage current value will be too large and an alarm will occur, most of which is caused by this cause. The correct wiring method of the residual current sensor can make the fire monitoring detector operate normally and effectively prevent the occurrence of electrical fires.