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Electrical Wiring in the Home/Ellectrical circuit breaker on neutral phases


I have installed multiple circuit breakers in my house electric supply. However there was a short circuit before the supply came into my home. Current surged in the neutral phase of the three phase supply. The banks of circuit breakers installed, did NOT trip. I am told that this was because the surge came in the neutral phase, which is not affected by surges and the circuit breakers did not trip. Much equipment was damaged.

My question is What equipment or breaker can I  install on the neutral incoming line to prevent such an occurrence ? The in comImg power is a 20 KVA, 220 Volts.

I was going to ask where you were because we don't have three phase in houses, generally speaking, maybe somewhere that once had a commercial or industrial use. However, you mentioned India.

I am not familiar with Indian wiring practices, but the several references I could find suggest 240 volts single phase for residential use. At 240 volts 20 kva is only eighty amps or so. With the allowances we use here that would mean a rated continuous load limit of about 65 amps.

I cannot imagine why three phase would be needed for this small a load.

In any case, we do not fuse our neutrals, for safety reasons outlined in our National Electrical Code. We used to but stopped the practice 70 or 80 years ago.

The information you were provided sounds doubtful to me. Without further information and no experience of your electrical practices, I can only tell you what I would suspect if the same event occurred here.

Since three phase power there appears to be provided at 440 volts, I would suspect a utility error. Have you asked any of your neighbors who share the same power source if they had a problem?

Also, I would want more information about the location and nature of the referenced "short circuit."

Good luck


Copy and paste link below-

It leads to a version of the Indian electrical code [as far as I can tell from what I read]  
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Robert Wilber


Licensed Philadelphia electrician serving Delaware, Chester, Montgomery and Philadelphia County in Pennsylvania. I install and repair residential, commercial and industrial wiring and lighting. Troubleshooting and repair of problems that stump other people is my favorite. I am willing to help people figure out why things don`t work. I understand motor controls, transformers and machine wiring. I do not teach basics to novices or do free design work.


Experience in the area I have 44 years experience in residential, commercial and industrial electrical construction and repair, 480 volts and below. This is not to be confused with one week repeated two thousand times.

44 years experience in residential, commercial and industrial electrical construction and repair

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