Inverter power supply

I have a '92 Sea Ray 200 that I'm putting an inverter into. Instead of messing with cirucit breakers and running a ton of wire, I plan on switching a starter soleniod from the helm between the batt and the inverter. I will tie the switch wire into the CB panel. Are there any problems with this since the inverter is fuse protected? Also, please set aside the battery draw and amp/voltage issues for the application.

Electrical issues are my crux; many cases have been spent over these.

Re: Inverter power supply

Howdy, FlyinGuy.

Welcome to iboats.

Don't use a starter solenoid for that, FlyGuy. They are made for intermittent, short cycle duty and would probably burn up if kept engaged for more than a few seconds at a time.

A 12V relay that latches in and has a seperate coil to unlatch sounds like a better solution. Be sure that the contacts can handle the inverter input current and are continuous duty.

Good luck.

Re: Inverter power supply

I'd go for a solid-state relay, but that's just my preference for damp locations.

Re: Inverter power supply

But you still need a fuse to protect the wiring to the relay and then the inverter.

What if you have a short in the wiring? Without a fuse or circuit breaker you have big problems.

It could be something as simple as an inline fuse near the battery, but you need something

Re: Inverter power supply

I considered relay's, but I can't find any SPDT's any larger than 40a.

I keep going back and forth in my mind: the inverter is 30a CB protected, but is hooked directly to the bat...but the same inverter can be powered thru a cigar lighter outlet...but the bat has 800a+ available...but it's only a 50a alternator...

I've thought myself into a circle. If it were my truck, I'd wire it directly to the bat and have a nice day. In the boat I want it switched from the helm and CB protected on both the switch leg and pole sides.

Sorry guys, I'm just a little fuzzy on this one.

Re: Inverter power supply

FlyinGuy1017 said:

I considered relay's, but I can't find any SPDT's any larger than 40a.

I keep going back and forth in my mind: the inverter is 30a CB protected, but is hooked directly to the bat...but the same inverter can be powered thru a cigar lighter outlet...but the bat has 800a+ available...but it's only a 50a alternator...

I've thought myself into a circle. If it were my truck, I'd wire it directly to the bat and have a nice day. In the boat I want it switched from the helm and CB protected on both the switch leg and pole sides.

Sorry guys, I'm just a little fuzzy on this one.

Click to expand...

Why do you need SPDT?

If the inverter os 30A, you should provide a circuit that can deliver continuous 30A.

A start solenoid (SPST) will indeed fail after a few seconds, as noted previously, so is not an adequate setup. It is designed for intermittent operation. The latching coil would fail.

The cigar lighter feed is for those applications that will not tax the system; the cig outlet circ protection would blow to save the wiring before even approaching the capacity of the inverter you mention. Obviously the cig outlet could not handle the amps you suggest.

The alt has NOTHING to do with it.

Just because the batt has a lot of amps available does not mean you need to size the conductors or circuit for that. The drinking water system from Niagara Falls does not need to accommodate the flow of the falls.

You do need to design for the amps used, and for the duration of the switched connection. How many amps, and how long?

Better to run proper marine grade wire with appropriate circuit protection. A Marine grade Ckt Bkr is available for your application. Use it as a SPST setup, eh?

Re: Inverter power supply

A solid state VSR with built in CB with manual override is the answer. High amperage (up to 150) and waterproof. And it will protect inverter from undervoltage.