Ceiling fan tripping earth leakage.

**adrianh** · 29-Sep-19, 01:52 PM

I would think that when the circuit is broken a couple of things might happen:
1. There would be a spark in the switch causing a transient into the motor coil.
2. That transient may be high enough to to cause a short in a moist or already compromised environment.

Maybe one of your motor coils has failed.

I had a similar thing with one of my CNC machines. It would run happily for hours on end and only trip when I turn the main power off. After much stuffing about and replacing many components did it come to light that the coolant pump had failed and I suppose the excessive magnetic field built up in the motor coil with the addition of the switch opening transient field was enough to short the pump to ground.

Dunno - may be I am talking rubbish but it seems to be the only thing that makes sense.

**AndyD** · 03-Oct-19, 11:44 AM

There may be high standing leakage from other circuits and the arc caused when you switch the ceiling fan off is enough to cause tripping.

**Derlyn** · 03-Oct-19, 04:04 PM

Bit of feedback.

Definately a fault with the fan.

There are another 5 fans on the same circuit and it's only this one causing the earth leakage to trip.

Have megger tested it ok. infinity .

Have removed the fan and replaced it with another ( same make and model ) ..... problem solved, but it still remains a mystery why.

Will start playing around with it in the workshop when time permits.

Regards ... Derek

**ians** · 03-Oct-19, 06:39 PM

IF you have done an insulation resistance test and it is clear ...my guess would be one of the capacitors are faulty... (without actually checking the fan it would be just that ...a wild guess) or a pinched wire...this is why i have a current leakage tester.

**AndyD** · 08-Oct-19, 10:27 PM

Earth leakage breakers can be a bit skittish. I had issues with one that used to trip every evening when the council street lights switched on. They can be a bit sensitive to phase angle fluctuations upstream as well as downstream especially with switching of highly capacitive or highly inductive loads. Usually a different brand of earth leakage breaker sorts it out but in your case it was probably just easier to replace the fan.

**adrianh** · 09-Oct-19, 10:45 AM

Originally posted by AndyD

Earth leakage breakers can be a bit skittish. I had issues with one that used to trip every evening when the council street lights switched on. They can be a bit sensitive to phase angle fluctuations upstream as well as downstream especially with switching of highly capacitive or highly inductive loads. Usually a different brand of earth leakage breaker sorts it out but in your case it was probably just easier to replace the fan.

Next time I will ask you first before speaking a lot of $h1T :-)

**ians** · 11-Oct-19, 06:19 PM

Originally posted by adrianh

Next time I will ask you first before speaking a lot of $h1T :-)

Actually your statement is not total bullshyte...nobody really knows the real answer unless a variety of tests are done using the correct equipment.

Comments made on a social media platform are merely suggestions.

Andy is also correct in what he stated... i wouldnt total agree with his statement ...but as i mentioned they merely suggestions.

**adrianh** · 11-Oct-19, 06:30 PM

Originally posted by ians

Actually your statement is not total bullshyte...nobody really knows the real answer unless a variety of tests are done using the correct equipment.

Comments made on a social media platform are merely suggestions.

Andy is also correct in what he stated... i wouldnt total agree with his statement ...but as i mentioned they merely suggestions.

Well I can tell you, sometimes the answer that solves a problem is really odd. I did a roughing toolpath on a cnc job last week and it was perfect. So I saved the file to a new revision today and made some alterations to the part. (made it a bit longer and added some elements) The CAM sotfware refused point blank to create the roughing path correctly. It would simply ignore large parts of the geometry. I spent many hours faffing with it - making al the parts nurbs, then nubs and meshes, then just a big mesh and and and.... I compared to the old revision and everything is correct (stock, bounding geometry etc). Then I turned the entire thing 90 degrees....Now the damn thing works perfectly. I have absolutely no idea why the stupid thing likes the drawing better landscape than portrait. It doesn't matter because I will place the stock accordingly. The point that I am trying to make is that the solution to the problem is totally irrational though it seems to be the only thing that works.

**Derlyn** · 24-Oct-19, 05:46 AM

Hi All

A bit of feedback.

Meggered the motor. Result infinity.

Connected the fan in my workshop and tested.

Turned it on and off a couple of times ..... no problem.
Left it running for an hour. When I turned it off, the earth leakage tripped.

While the motor was still warm, I meggered it again and found the reading to be lower than when the motor was cold. 1,5 megs.

The insulation resistance is reducing with an increase in temperature.

I am aware that the earth leakage should only start tripping when the insulation resistance is approx 8k or lower, but I suppose the reduction in insulation resistance combined with the arc from the switch does something that causes enough current to earth to trip the earth leakage.

I still don't fully understand the theory behind it, but I now know that it's the fan that's faulty.

Derek

**ians** · 24-Oct-19, 04:14 PM

Originally posted by Derlyn

Hi All

A bit of feedback.

Meggered the motor. Result infinity.

Connected the fan in my workshop and tested.

Turned it on and off a couple of times ..... no problem.
Left it running for an hour. When I turned it off, the earth leakage tripped.

While the motor was still warm, I meggered it again and found the reading to be lower than when the motor was cold. 1,5 megs.

The insulation resistance is reducing with an increase in temperature.

I am aware that the earth leakage should only start tripping when the insulation resistance is approx 8k or lower, but I suppose the reduction in insulation resistance combined with the arc from the switch does something that causes enough current to earth to trip the earth leakage.

I still don't fully understand the theory behind it, but I now know that it's the fan that's faulty.

Derek

Until you actually find the fault... you will never know....how does the saying go... clutching at straws.

something to consider...the motor turns...its hanging on a shaft... wiring gets warm (even if it doesnt get warm)...as the motor stops...the wiring shorts on the frame ...e/l trips...i would bet money on the neutral being the cause of problem.

The wires are always squashed through the tubes and out through a hole into a connector block... do you have a leakage current clamp?

if not...hang the fan ...connect the insulation resistance tester set to 1000 volts ...shake the bottom of the fan and see if the reading drops while doing this.

**natal21** · 02-Feb-21, 07:29 AM

Originally posted by Derlyn

Hi All

A bit of feedback.

Meggered the motor. Result infinity.

Connected the fan in my workshop and tested.

Turned it on and off a couple of times ..... no problem.
Left it running for an hour. When I turned it off, the earth leakage tripped.

While the motor was still warm, I meggered it again and found the reading to be lower than when the motor was cold. 1,5 megs.

The insulation resistance is reducing with an increase in temperature.

I am aware that the earth leakage should only start tripping when the insulation resistance is approx 8k or lower, but I suppose the reduction in insulation resistance combined with the arc from the switch does something that causes enough current to earth to trip the earth leakage.

I still don't fully understand the theory behind it, but I now know that it's the fan that's faulty.

Derek

This is why i always said , "electricity is a mix of science and magic"

**Polycab** · 04-Feb-21, 09:04 AM

Hello, There

Ceiling fan tripping earth leakage may be it is happen due to the poor wiring or also due to the earthing problem in house. One of the simplest grounding problems to fix is making sure that all ground connections are correct.