Help with Automatic Transfer Switch Repair (buck converter)

Thread Starter


Joined Sep 14, 2015
Hi there,

I blew my ATS over the weekend.

Opened up and found no voltage flowing beyond the voltage regulator. I need some advice to replace or fix.

The ATS is a 'MoesHouse Automatic ATS Dual Power Transfer Switch'

Here is a photo of the voltage regulating module removed from the board.


It is covered in silicone but hopefully enough there to ID and advise.

I have hooked up 24vdc in and get zero volts out. I read voltage on the first two capacitors and none on the third. All capacitors charge on multimeter.

No idea how to fix or what spec a replacement board/module should be, but would really like to repair this ATS so I know I can fix if it happens again - and perhaps take some measures to prevent it happening again.

The input range is from 11v to 54vdc and the regulated output voltage is 12Vdc

My battery operating range is 18.5 to 24.5vdc , and whilst keeping the wider input range would be nice - I only need a range that suits my battery set up.

The failure was picked up after main battery wires were disconnected from the inverter and later re-attached. Perhaps inverter inrush caused a voltage spike?!

I'm trying to figure out if it is worth picking off all the silicone in an attempt to find a faulty component, or if I should look for a replacement/upgrade?

From the capacitor/coil and heatsync size can we have a guess at the spec required for replacement? It drives two fairly large relays and I have two much smaller 12vdc relays chained on also to handle some other switching tasks (which perhaps is another candidate for cause of failure)

Any pointers much appreciated - thanks.