surge arresters

It may not be the "surge" per se, rather poor circuit design when it is powered up handling
inputs and outputs of the main controller chip.

You could find the control line and build a power on delay circuit when power is restored,
would take some effort as probably no schematic available for it. But you know power fets
or bipolars are being controlled eg. their gate/base device connections being driven by the
control circuit.

You could always consider putting a PC UPS on it for power control.....Has to have enough power
rating, and this would handle a lot of the short term AC line power disruptions. Just a thought.
You could rent/borrow a clamp meter, they are actually pretty cheap, to see what the non operating
current/power drain is for the garage door opener to help you decide what size UPS to buy.


Note the opener may draw such low power even the clampmeter cannot pick up.
So a zero reading may be valid unless the clampmeter has good sensitivity

Or use a ESP8266/ESP32 to detect door open and send you an SMS to your phone.....whenever
door is opened.....




Regards, Dana.

Thank you , I will try & let you know, I have installed WIFI switch to operate the door with my phone App, Iwill disconnect it & try .

A surge arrester is a device to protect electrical equipment from over-voltage transients caused by external or internal events
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