Battery switch

snookhooked

Petty Officer 2nd Class
Joined
Aug 19, 2008
Messages
159
Being not sure on some wiring I must ask this so that I don't do the wrong thing. I bought a battery switch to run dual battery's . the wiring diagram is so small that its not the best to read. you have positive 1 and 2 which are for each batter and you have the common which is where I am questioning myself. what I need to find out is how the common it run? I thought common was ground like a dummy but them I was told it was like a positive. could someone please tell me how to run it? I don't have a a wire that goes to a switch. the old batteries where unhooked and the switch wasn't fully hooked up either so I didn't have any previous reference to go by. like I said the instructions weren't any help either so now I'm stuck and dont want to wire something wrong. would be greatful for some help from someone who has hooked this up before. Thanks
 

Barnacle_Bill

Admiral
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Feb 8, 2004
Messages
6,469
Re: Battery switch

For a battery switch common is the big red wire coming from the motor. No grounds on the seitch.
 

snookhooked

Petty Officer 2nd Class
Joined
Aug 19, 2008
Messages
159
Re: Battery switch

Ok, that makes sense but I will look again to make sure but the only red wire I know is the ground and positive that you normally hook up to the battery. Im going to go through my manual too. to be honest, I didnt even think to go there and look. I didnt think that it would be in the manual. Thanks
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Battery switch

Here is a typical battery switch setup for an outboard.

StandardBatterySwitchWiring.jpg


All of the accessories in the boat except the bilge pump should be wired to the COM terminal on the switch. All grounds can be connected to ground buss on the fuse/breaker panel or to either of the battery negative terminals.
 

snookhooked

Petty Officer 2nd Class
Joined
Aug 19, 2008
Messages
159
Re: Battery switch

Man that pic was great and I was just coming here to say that the red wire that was talked about went to the com. sometimes I get to busy thinking and when I sit down and mellow out, then it comes to me. lol impatience person I am. but now that I understand, I do have another question. you said that everything should run to the common but the bilge pump . it seems that I may be in the process of doing some rerouting on my wiring. right now Im on one battery and it controls everything. even my bilge pump that works off my main panel. or can I just keep everything on the one wire and since having two batteries, I would always have a back up and if the motor is running then I wouldnt loose power. give me your opinion. Thanks p.s. it sounds like it was never hooked up for dual battery's and they just added the switch to have two.
 
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snookhooked

Petty Officer 2nd Class
Joined
Aug 19, 2008
Messages
159
Re: Battery switch

Silvertip. OK, I'm going to revise my second question. I went back out and traced my wiring. I think what may have happen, was maybe something went wrong with the Perko switch or whatever made them do what they did? the red(positive) wire coming from the motor had a battery post clamp on it with the small red wire with it. If I am understanding you correctly. the smaller red wire is for the panel on the console that powers everything including the ignition switch. I will hook both those wires to the common on the switch and then run the other two power from the battery to switch one and two like shown on picture you sent then run the ground from the motor to the negative side of one battery the series the ground from that to the other battery. right? now that mean I would only have to reroute my bilge so that Im not going off the main panel in terms of power. it can be run through the panel but on its own power source right? what you have sent is pretty straight forward but just kinda double checking most of it and the bilge since you said you would run it separate. if I an understanding you correctly the common will continue to supply power from either battery? Thanks for the help and dealing with some crazy questions I may ask. Thanks again
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Battery switch

You have it right. You want the bilge pump (provided it has an automatic switch) directly to the battery. If you had it wired through the battery switch it wouldn't run if you got water in the boat. Obviously if you don't have an automatic bilge pump, it can be wired to the COM terminal as well since it wouldn't run unless you turned it on manually. The reason you want the accessories on the COM terminal is this provides you the opportunty to run on BOTH while you are boating so both batteries will be charging. When you anchor or stop to fish, have an adult beverage or whatever, you can set the switch to BAT #2 so it will feed the radio and all the accessories while you are stopped, thus saving the start battery. When you are ready to go, if you ran down BAT 2 you switch back to BAT 1, start it up, then switch to either BAT 2 or BOTH and away you go. Remember, the switch is versatile, so OFF turns everything off. BAT 1 means ONLY BAT 1 is on line and only it will power accessories and be charged by the engine. Same for BAT 2. In BOTH, both batteries are on line, both are powering your accessories and both will be charged underway. There are many other ways to connect things but this is the most common and most versatile. It's just that lots of folks get really confused over what position does what. All you need to do is think of it as electrical system #1, electrical system #2, or BOTH.
 

snookhooked

Petty Officer 2nd Class
Joined
Aug 19, 2008
Messages
159
Re: Battery switch

Hey Silvertip, I 100% agree with what you said. after reading and giving a little bit to soak in, then I fully understood you and your reasons. now I don't have a automatic bilge pump. I hear the auto like to drain batteries so I opted with Manual. all that means is that I will have to keep a eye on it and that's no problem here. I just came back from the Boaters World closing sale which will last about 3 months and really got some good deals. I bought what all I need to complete this switch job. Thanks soooo much for the help and you made everything so easy to understand how to do and why. Thanks so much!!!! oh yeah, it says to never run the motor with the switch in the off position for this will damage the motor. I read that somewhere. Thankful I seen that because it will make me think to check it before I take the boat out but so far there is no drainage of the batter so I may just leave it on the number one position.
 
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