Need help with relay options

I am working on a van conversion. I have both 12V and 120V circuits (provided by inverter). I would like to be able to control a 120V outlet that will power a hot water heater via a lighted 12V switch. I am thinking a relay is the way to accomplish this, but I’m not sure what one would work. Thx!!


Would you know the maximum current the load side of the relay may see?


If not, we do have a fair number of option that can work.

However it would help to know the current the water heat may end up needing

You’ll need to figure a current rating requirement based on the rated power of the load, but most electric water heaters will want something on the order of 15A. A relay rated to switch at least that @ your 120V would be a minimum. While a single-pole unit could likely serve, I’d suggest a double pole since they don’t cost a great deal more and offer some advantages in a situation like this. HE2AN-Q-DC12V might be a good choice.

Some illuminated rocker switches that ought to be compatible with 12V can be found here.

Note that getting 1500W from a 12V source implies upwards of a 125A current draw, plus conversion losses. Do take that into account…

Terminals for that relay WM18241-ND

Tooling for that terminal WM18730-ND

The water heater is rated at 11.3A

The relay Rick suggested then would work nicely.

Thank you all for the quick help! Much appreciated!!

I was looking at the relay recommended by Rick…it looks like that one is a DPST? Would a SPST be a better option? How about something like this RELAY?

If that would work, does digi-key sell one of those? Thx again!!

That solid state relay will generate a bunch of heat, which means wasted electricity, that’s why it has an enormous heat sink.

An electro-mechanical relay like Rick recommended will not generate significant heat so will not be wasting electricity.

SPST would not be better but it might be cheaper.

Thanks! Appreciate the help!!