What is this Electrical Part

[scottinsydney]

There are three of these oversize relay type parts in the lower section of our AC Distribution Panel.

They seem to click a bit when the genset is switching on/off or when we switch to the inverter.

Given there are three AC sub panels, I guess there is one gizmo for each.

I showed this photo to the guys at Sam's when I was in Florda in February. They did not know what it did but said it was very expensive!

What is it please?

 

[jmooney]

This controls the voltage warning on the systems alarm panel . Over or under voltage.

 

[scottinsydney]

But the systems alarm panel is 32 volts? Is there actually an alarm/light on the monitor that alarms when AC is unsteady? I've never noticed it.

 

[MadHatter53]

My alarm goes off when I lose commercial power or my dc voltage drops.

 

[jmooney]

But the systems alarm panel is 32 volts? Is there actually an alarm/light on the monitor that alarms when AC is unsteady? I've never noticed it.

Yes , the light is AC on the warning panel .

 

[Kquaine]

It is a voltage sense relay. Relay will pull in when (energize) when an ac circuit is greater than 90vac but less than 135vac. It is probably used for the ac power loss fault on alarm panel

 

[scottinsydney]

I looked on the systems monitor panel and yes, there is an AC light. I don't think I've ever seen it light up.

#1 old Kohler genset removed from boat.
#2 old kohler genset removed from boat and replaced with 120/240v Phasor.

AC light has never lit up or alarmed.

 

[Kquaine]

I looked on the systems monitor panel and yes, there is an AC light. I don't think I've ever seen it light up. #1 old Kohler genset removed from boat.#2 old kohler genset removed from boat and replaced with 120/240v Phasor.AC light has never lit up or alarmed.

Assuming your AC source selection panel is like mine, you should see a selector switch near the very bottom of each of the 2 selector panels. I believe it is called ac sense or something like that. I’m going by memory. This selector switch enables or disables the 120 vac alarm monitoring for the alarm panel. If the alarm does not come on when shore power is disconnected then flip the switches to the other position. Assuming the power relay you showed above is installed and working properly.

 

[Sadey]

A.C. Power Monitor switches. Panel is not complete because I’m in the middle of an inverter install.

 

[rwaldrop13]

Well another Pau Hana mystery - Our electrical panels didn't have any of those.