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Battery Switch Help

Old 06-02-2016, 04:46 PM
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Default Battery Switch Help

Im having trouble trying to get my battery switches to work properly. I am trying to get the house batteries to charge when the motors are running if i switch the battery switch to both batteries.

Ok so bare with me.

I have twin outboards, running 4 batteries, 2 starting and 2 house batteries tied together as one big 12V battery. Below are pics of the back of the switches

From left to right, the heavy red wires go to the batteries and the darker red goes to the main breaker panel. Bottom is the face of the switch panel so you are looking at the back of the wires when its upside down.

Left to right, Starting battery 1, House battery, hot wire to main panel, Battery 2

Old 06-02-2016, 09:52 PM
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where are the engine cables? why is your house feeding what appears to be the common output of the engine switch? you'd want a 3rd swtich for the house. your DC panel is being feed by 3 breakers in parallel?...

the way it's currently wired (wrongy) the right switch basicly does nothing. it does nothing in 1 or 2, in both in joins the 2 engine batteries. (but so can the left switch) this should be left off.

the left switch. normal operation would be switch off. house and engine batteries isolated.

on "1" engine one will charge house. on 2, engine 2 will charge house battery. on both. all 3 batteries joined together.

so basically your 2 main switches are normally left off which makes not sense.
Old 06-03-2016, 07:32 AM
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My first thought is that start 1 should go to breaker 1, house to breaker 2, start 2 to breaker 3, only if the breakers are capable of handling the load of the starter. Otherwise I don't see their purpose.

The output of breaker 1 and 3 should go to position 1 on the respective switches and also to position 2 on the other switch. That way position 1 is your standard everything is OK on both switches and in an emergency you can switch to position 2 and start off the other battery. You'd get an ACR and tie into the common/output of one of the switches and run that to the input of switch 2 or the house battery itself, which will let you charge the house system when that engine is running. You could also get two ACRs and let both or either engine keep your house topped off.

You can make this work but it can be done more correctly by starting over with a new panel and switches/components.

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