The reason and maintenance method of leakage of constant temperature and humidity machine

The refrigeration system of the constant temperature and humidity machine is normal, and the box leaks electricity. The reasons for this failure may have the following four aspects:

A. Induction leakage

The constant temperature and humidity machine is refrigerating normally, and the hand feels numb when touching the box. The reason for this phenomenon is the induction leakage. The compressor and the internal lighting circuit of the constant temperature and humidity machine all pass through the box and the inner wall, and there is a certain distributed capacitance; the compressor motor is an induction motor, and a self-inductive potential is generated on the rotor. At this time, the constant temperature and humidity machine is not reliable. The ground wire will feel numb when people touch the box.

B. Compressor leakage

The compressor motor winding and the casing are short-circuited, causing the box to leak. The compressor leaks electricity, and the box voltage is high, close to the power supply voltage.

C. Thermostat leakage

Most of the thermostats of constant temperature and humidity machines are installed on the inner wall, and the temperature change in the box will cause condensation around the thermostat. When the condensed water flows into the thermostat, the resistance value between the thermostat contact and the box drops, causing leakage.

D. Leakage caused by damage to components or aging and damage of wires

Repair method:

1. Check the user's power supply connector, whether the grounding is normal, and whether the grounding wire is short-circuited;

2. After the power is turned on, check whether the cooling of the constant temperature and humidity machine is normal, and whether there is obvious numbness when touching the box with human hands;

3. First check the insulation of the compressor, and use a megohmmeter to check whether the resistance to ground is ≥20MΩ;

4. Check the insulation of suspicious components, thermostats, lamps and external circuits