Repair Heating Coils of Electrical Appliances

Festive season is here. It is time to bring out that electric deep oil fryer or the Baby Belling oven from the store to make some cookies. Switch it on and it trips the earth leakage circuit breaker and cuts the power to the house.

Moisture trapped inside the heating coil of the electrical appliance had lowered the insulation of the coil. That caused higher than normal current leakage to the earth wire and tripped the circuit breaker.

How the Circuit Breaker Works?
The circuit breaker constantly measures the differences between current that flows into and returns from the house. Current leakage, if any, flows directly to the ground. When the appliance's current leakage to the ground exceeds 30 milli-ampere, the circuit breaker will trip the power supply and protect humans against electric shock;

Why 30 milli-ampere?
The research and experience found that this is the safest level of electricity that a normal human can withstand without suffering any injury.

How to Get Rid of the Moisture?
By heating. To enable the heating coil of the appliance, one must first remove the earth wire or the green wire; otherwise, it would continue to trip the power supply.

Isn’t that Dangerous?
It is not dangerous if there are sufficient controls to ensure that one would not come into contact with any metal work of the appliance;

Are There Any Better Method?
No. Removing the coil to be heated separately is not a good solution.

How to Remove the Moisture Safely?
1. One would need the following tools:-
a) A two pin adaptor that would accept a 3-pin socket outlet as shown;
b) A test pen
These 2 items are available from the local stores

2) Plug the adaptor into the wall socket outlet and then turn on the appliance as usual;
3) Do not touch any metal works. Use the test pen to touch any metal work; note the brightness of the neon lamp in the test pen;
4) After about 10 minutes, use the test pen again to test. One should note that the neon lamp will get weaker; meaning, the insulation of the coil is improving with less electricity leakage from the heating coil;
5) Now, plug the appliance without the adaptor. If the appliance has no other fault, it should not trip the circuit breaker this time; if not, repeat the heating.

No comments: