Can load shedding damage electrical equipment? My motorbike buddy lost 2 garage door motors recently. He is convinced that it is because of load shedding. The insurance company has a different view and refuses to pay. What exactly happens at the moment of disconnection and reconnection to the grid parameters? My view is that the frequency will not be affected. I also believe that during reconnection the voltage will not be able to spike because of the huge load on the grid after load shedding. So if I am right the only problem could be low voltage for a while. Can this lead to damages to electrical equipment or is there other issues I am not aware of?

1 hour ago, Fuenkli said:

Can load shedding damage electrical equipment? My motorbike buddy lost 2 garage door motors recently.

Garage door operator motors these days are DC motors. If it's an old system it could be an AC motor. Which one burnt out?

13 hours ago, Richard Mackay said:

Which one burnt out?

not sure. It just stopped working and the company he called to fix it told him that it is cheaper to just buy a new unit instead of trying to repair it. 

Edited February 29, 20206 yr by Fuenkli

I suppose it is going to depend what kind of door opener it is, and what it is that broke. My old house had these ET DC Blue door openers. That had a good old chunky toroid in the back and the motor ran off 24VDC. There was little that could go wrong with that thing, the low frequency power supply could absorb most spikes just fine, and it had a triad of MOVs in it too for that.

But... on the day that I moved (Thursday 30 January ) load shedding came back, and one of the very first things that happened, partly due to the removal of the backup system, is that the electric fence energizer failed (just as the new owner took occupation). Now that could be... because over the years the littler internal battery got dry as a bone and it could hardly backup the lowly 10W support for even 10 minutes... so maybe it was simply the slow gradual wear over the years that adds up and pushes it over the edge during a power failure... but... it is certainly my anecdotal experience that things do and can fail due to power failures, but perhaps not solely due to the power failures.

19 hours ago, Fuenkli said:

Can load shedding damage electrical equipment?

Yes, very much so.  You can have surge when the power returns, and also because everyone in your street's geysers and pool pumps come on the supply can be erratic for a few minutes after power returns (or at least that is how I understand it anyway).

For example there is an Ellies fridge intelligent surge protector which will only supply power to the device some minutes after the power has returned.

Interesting that the insurance wouldn't pay, one of my folks garage door motors went after loading a little while back, and the insurance did pay.  In fact they sent someone around and just replaced it.

Not sure who they are with, but I expect it very much depends on the fine print in the policy.  I just had my house insurance moved to a different broker, and the new policy was over 20 pages long, and there was a section that covered surge.  It's a pain, but you should always read your policy document carefully to avoid tears down the line.

I have an ancient AC Coromaster garage motor.  After load shedding a week or two back all its settings were reset.  The open and closed positions were defaulted about two centimetres away from each other in the closed position.  It was an absolute b@stard to set it correctly.