Shock neglected causes smoke

The Inverter in my home, which feeds all the lighting and fans had tripped when I came home on Thu evening. I tried to reset and it was showing fault even when I isolated it. I called up the support and they were quite helpful, had to get the serial and model number, which required hunting for torch and reading glasses. The support person waited patiently thru all this and helped me put the Inverte back in circuit and it worked. He thought it could have been an momentary fault, I was happy too.

It tripped again in night and I reset it and it was back in action.

I woke up today morning and found that the inverter had tripped. I decided to feed the home directly and investigate later. To isolate the Inverter I turned off the mains, after isolating I turned on the mains, a strange noise started in the switch box. I just happened to look at my gate and saw that one of the gate lights, which was fused and not in use for a long time was smoking! It was unnerving, I switched of the mains and called my electrician. My electrician surmised that some water must have gone in due to rain (it was raining) and causing this. He advised me to remove the lamp and tape the wire ends with insulation and also asked me if I had reversed the phase. I was supposed to reverse the phase after I got a shock and had not done that. See this post.

I removed the lamp and taped of the wire ends and switched on the mains. In the mean time my sister came and turned on the switch for the lamp just removed and again smoke! Called my electrician, he asked have you reversed the phase? I had not.

I went and looked at the wire that connects the Inverter to the home circuit, it is also used to connect directly. There were two wires - red and yellow, I would expect the red in left plug and yellow in right plug, it was reversed. I changed and tried, all was fine. I got the Inverted back in circuit and it is working since then.

Guess that the wiring to the unused lamp had some leakage, aggravated by being live all the time due to phase reversal and rain. The problem is still there, but will not show up till the switch is turned on. I did try to turn on and check, no smoke, no glow with a tester on the iron pipe having the wiring and the lamp mount, it seems OK, but will get it checked by the electrician.

The phase reversal happened when the Inverter was installed, will inform their support, as it can be quite dangerous.