Perko Dual Battey Switch

[SHickey]

Hello all,

I have a couple of questions regarding a Perko dual battery switch. I have two batteries for my boat but I am not exactly sure how I should hook them both up to the switch. My plan is to use my better battery for the majority of the work and keep the smaller one for emergencies or when anchored.

Does anyone have a diagram of how the batteries should be hooked up to the switch?

When I am running my boat, should I keep the switch only on #1 the better battery, or can I keep it on the "ALL" setting so that both batteries keep recharging while underway?

Can you change the battery selection while the motor is running or do you need to turn the motor off before changing the selector?

I am not well versed with electrical knowledge and do not want to damage the batteries or alternator if I don't know what I am doing.

It does say "Stop Engines Before Switching Off"

Thanks

SH

 

[UncleWillie]

Re: Perko Dual Battery Switch

Re: Perko Dual Battery Switch

Batteries go to posts #1 and #2.
Engine goes to "Common".

Start on #1, #2 or "Both", your choice.

When stopped, select #1 or #2 to save the other battery to restart the engine.

When running Select "Both" to keep both batteries charged, Both will charge independently of the other.
One Full and one Low is not a problem, both will charge until full and no more.

When running you can switch from #1 to "Both" to #2 and back.

When Running DO NOT switch from #1 to "OFF" to #2! :grumpy:

It says "Stop Engines Before Switching Off" because without a battery connected to the system the alternator will loose regulation and deliver 20+ volts to all your electronics, including the engines ECU if so equipped.
1/100th of a second later, everything smokes.

Installing an ACR eliminates all this tedious and careful switching.
You can't mess up accidentally.

 

[wrench 3]

Re: Perko Dual Battey Switch

This picture shows the basic wiring.

The rest of the boat(lights accessories etc.) would be connected to the common on the switch. You would normally run on both, so that both batteries charge. You can switch with the engine running as long as you don't go to the off position.

 

[SHickey]

Re: Perko Dual Battey Switch

Thank you both for the advice and the wiring diagram. Now it makes much more sense. I will be very careful switching my batteries while I am running and will most likely leave it on the "Both" setting unless I am anchored for an extended time.

You guys are the BEST!!

SH

 

[Silvertip]

Re: Perko Dual Battey Switch

There is no "best way" to run the switch. Consider yourself a traffic cop but in this case you are directing which battery needs charging and which battery is running things. There is no reason to be continuously fiddling with the switch. If you don't have a trolling motor, why not just alternate which battery you use that day. That keeps both charged and both get to serve the power needs of the boat and hence batteries last longer. If you have a trolling motor, which battery you select is a little more important but consider selecting battery 2 (the troller battery) before you leave the dock. It will then be charged when you get to the fishing hole. Even if you move around a lot, the engine will be adding a bit of a charge each time. Keep in mind also that unless your engine has a high capacity alternator you will need to run wide open for hours to fully charge a deeply discharged troller battery. It is therefore advised that you install an onboard charger of 5 - 10 amps for overnight charging. No -- trickle chargers are not the answer. Again -- if you have a low output alternator, it does little good to select BOTH as only one of the two batteries will actually need more charge. Pick that one so it gets maximum charge. All you need to do is think a little about which battery will get the most use during the day and select that one.