1. The whole machine can't be turned on and the power cord or fuse holder is not in good contact.

| Check the circuit, find out the reason and solve it.
Phase-sensitive zero adjustment failure phase-sensitive rectifier wiring or part of the rectifier diode performance does not

| check the line or replace components.
3. The calibration value of the sensor is not or very small.
(1) The oscillator stops vibration or has poor contact. | Measure the oscillating voltage of the sensor and repair the circuit.
(2) The amplifier is faulty. Maintenance amplifier.
4 Sensor Failure
The connection of the sensor and the plug socket are not in good contact. If all other sensors fail, the contact between the connection and the plug socket can be checked.
(2) The sensor is damaged by dampness or overload. | (2) Sensors should be repaired or replaced.
5 The balance circuit of the bridge can not be adjusted. There is a fault in the balance circuit. Check the connection of line, band switch and potentiometer.
Six zero drift (1) Individual sensor temperature compensation is not good. (1) Change other sensors for comparison and maintenance.
(2) The sub-heating time is insufficient or the ambient temperature varies greatly. (2) Increasing the sub-heating time or stabilizing the ambient temperature.
(3) The oscillator amplitude is unstable. | (3) Maintenance circuit and steady-amplitude thermistor (it can only pass a few milliamperes of current, so special care should be taken in detection). Http://www.kuaijc.com/
(4) Voltage fluctuation of power supply is too large. | Maintenance of voltage stabilized power supply.