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At my home after the lightest thunderstorms we end up losing ceiling fans - they fail to rotate. The fans' winding gets damaged despite power cuts enforced by the power supply company (they cut power during thunderstorms) and we turning off the mains. As a result, during every rainy season, we end up repairing all our fans multiple times.

We are often told by electricians that -

  1. This is common in RCC ceilings as the surge often travels through the reinforcement's iron rods and ends up making a contact with the hook that hangs the ceiling fans
  2. There could be some wiring issue

How can I troubleshoot this and ascertain the root cause?

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  • 1
    Where are you from? I have never ever heard of this. Fascinating though. You sure the electric company doesn't run the ceiling fan company?
    – DMoore
    Commented Jul 16, 2016 at 7:04
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    I'm from India. No, electricity company doesn't run ceiling fan company. :)
    – Chethan S.
    Commented Jul 16, 2016 at 7:10
  • You say this happens after a rainy season. Might be corrosion of the brushes from high humidity?
    – bigbull15
    Commented Jul 16, 2016 at 15:54

4 Answers 4

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It's an open secret, that No standards are followed in India, and none of the electrical or any other work is up to code.

I too had a similar problem in the apartment that I was renting in Bangalore. Every-time there was lighting and thunder, first the power used to fail, and some of the lights used to flicker, and couple of times the winding of my ceiling fans got burned, and had to be replaced.

I had a couple of electricians look at it, but they were of no help. That's when I decided to take things in my own hands, and investigate. What I found was horrible.

  • In several places, the switch was not on the live, but on the neutral. This meant that often the appliances were live, (had a potential of 220v) just the circuit was not complete.
  • The circuitry of the building was such, that there was a return current on the neutral, even when there was no electricity. This was probably due to wiring of two apartments sharing a neutral, and they having an inverter, or something.
  • The earthing was probably just the neutral, or the earthing plate was not properly installed.

I had to take the following steps:

  • Get a proper earthing plate installed, and connected.
  • Install a high quality electronic circuit-braker. I forget the exact details, but I think, it was dual pole & checked for the leakage current in the earthing.
  • Fix the wiring, to make sure all switches were on Live, and no appliance/connection was ever live with the switch turned off.
  • Have new wiring run to the fans, which included an Earth, which was connected to the hook that the fan was on, as well as the rod of the Fan.

After this, I never had any issues.

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    Sounds rotten! Thanks for the insight into the mess out there, BTW Commented Jul 17, 2016 at 23:55
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    I believe the fancy breaker is a surge suppressor, 2 of the houses I rewired were in Ohio, both wired backwards/ white was hot and black neutral but the switches were wired to the black. Bad wiring must be more common back there than I thought.
    – Ed Beal
    Commented Jul 18, 2016 at 13:43
  • A faulty earthing system would definitely contribute to this -- the main job of the earth electrode itself is to limit common-mode surges on the power network to not-insane values Commented May 7, 2017 at 4:46
  • From what I've heard from many sources about the power utilities and wiring jobs in India, I'm amazed there are 1.3 billion people still alive.
    – fixer1234
    Commented May 7, 2017 at 4:51
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Wow I haven't heard of fans being damaged like the issue you are having usually computers and digital devices are damaged well before a motor is. A whole house surge suppressor would help to reduce line spikes. There are many different brands and sizes, they get more expensive as the size of the spike they can dissipate goes up, measured in Joules. When installed at the service panel they provide the best protection.

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I had an experience. In our Mosque (3 Storied Building) after a heavy lightning almost 9 Ceiling fan's winding were damaged.But none of the bulbs and any other electric devices were damaged. The electric wiring had no problem.

After detailed checking I realized that Reinforced steel members were exposed at the top floor (above 3 floor) and the ceiling fan hanging rod was touching the hook. Since hooks are connected with reinforced steel members the high voltage may be came through that and it might be the cause for winding damage. Two three Ceiling fan was working and their rod was not touching the hook.

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The cause is high common mode voltage between the electrical system and the structure. The question is why? India usually use a TN-S earthing system, meaning the earth bond providing the reference for the electrical supply is external to the property. During a lightning storm, quite high voltages can exist between two points in the ground (or in this case, between your building and the electrical supply).

The remedy is to connect the earth bond from the electrical supply to the fan body. Usually the fan will have a screw with an earth symbol for this purpose. This will place the fan at the same voltage as the electrical system, preventing insulation damage during storms.

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