Auto Transfer Switch

[km1125]

If they don't default to shore power, I'm surprised. Normally they active by the power from the generator. If you see them activate from shore power then it would be the bottom set of contact for shore, and the top set for generator. However, if it's not even moving, then it's the coil and not the contacts.

What I was seeing in the pic in noted by the red arrow. Looks discolored. All four contact are circled but there are two sides, the top and bottom to each one. I agree just replace it if available.

ats2_circles.jpg

[chpsk8]

I had a similar problem on my '95 355 Aft Cabin.
Shore power two would not supply power on generator. It would work fine on shore power.

Thanks to this thread I was able to track down the auto switching relay. It was in my electrical panel at the top behind the volt/amp gauges.

When I took the panel apart there were two burned out wires. I believe they shorted due to an issue with the shore power cable not being tightly connected and shorting out at some point. I went to West Marine and bought some 600v cable and replaced those wires and at the same time replaced the auto relay using the Amazon link referenced earlier.
The part was called "NTE Electronics R04-11A30-120 Series R4 General Purpose Multicontact AC Open Frame Relay, Heavy Duty, DPDT Contact Arrangement, 30 Amp, 120 VAC"
It was a perfect match. I killed all power to the boat including the 12v sources. Checked the panel for voltage and then dove in and swapped out the part. Pretty simple to do. Just change one wire at a time and work clockwise around the relay until everything is done. I tied back a couple stray wires just to make it a little neater in there.

Thought I would loop back on this just in case anyone else has the same issue and just add my experience.

[buster53]

Ok, old thread but I'm having a problem on my boat. I'm not getting shore power on either of my 30 amp connectors. Everything works on genset. Any possibility both transfer switches went bad at the same time?

Edit: Problem solved.

[RGrew176]

Qr Bbpost Ok, old thread but I'm having a problem on my boat. I'm not getting shore power on either of my 30 amp connectors. Everything works on genset. Any possibility both transfer switches went bad at the same time?

Edit: Problem solved.

Please post how you solved the problem. It could help someone in the future.