The new boat has dual batteries with a Perko dual battery switch (the one that has OFF - 1 - ALL - 2). Previous owner said he always ran the boat in the ALL position.

If I do that, doesn't both batteries get put in parallel? I don't think that this is the best way to run/charge the batteries. I've read that you should select one (or the other!) battery and then use a different battery each trip to keep both in good shape. Only use ALL when one battery won't start the motor. What is the proper procedure?

I also know that you NEVER want to move the switch to OFF when the motor is running. This will create an infinate load situation and blow the alternator.

Also wondering how you manually charge a battery with a battery charger. Do you put the switch to OFF and connect the charger to the battery you need to charge? Can this damage the alternator? Should I disconnect the battery prior to manual charging?

Thanks,

Jim

Jim,
Normal running you have it right, alternate batteries. If one battery is down and won't start the motot DO NOT put the switch in the all position, it will allow the strong battery to drain into the weak one. Just put the switch on the number of the strong battery. You can attach a charger with the switch in the off position, or if you wnt to chage both batteries put the switch in the all position.

The answer to your question involves a deeper look. My Rude Ficht has an alternate charging post that I wired myself and both batteries are getting charged while running no matter where the switch is, I dont believe battery switches were intended for the purpose of charging one over the other, more of a way to control which battery you use for a certain load, ie: starting=cranking battery versus accessories=deep cycle battery and when your battery gets down you have a way to start your motor by combining the two.

By the way I have always charged my batteries with a charger and never worried about battery switch position.

VectorfisherI just picked up my new Parker last weekend and got the low down on daul batteries fron John , one of the mechanics at Ocean House Marine. He seems to known his stuff and what he said is in agreement with Vectorfisher .I have the same swiych so it should be the same for you. Batter 1 should be used only to start and run the motor. Battery 2 should have all your electronics and bilge pump hooked up to it. If battery 2 goes dead some electronics will have to be recalibrated. So I was told to only use 2 if battery 1 goes dead. Both batteries will be charged regardless if the switch is on 1 - 2 or both. This switch is only to start the engine. RAM

When running use ALL position so both batteries charge from alternator. I have a start battery on #1 position that I use for starting only and I have a deep cycle battery on #2 position to run my electronics when the motor is off. This is the proper way to do it. The start battery provides more cranking amps needed to start the motor where as a deep cycle will run your electronics longer and can handle a total discharge unlike a starting battery.

I usually run with my #1 battery. Every couple of trips I use the #2 battery just to make sure it is fully charged.

Geez, you're getting all kinds of info here - let me confuse you more.
Are both batteries the same? If so, alternate between the 2 like they said above.
If one is a starting and the other a deep cycle - then it's clear.
BUT, I can tell you this: on MY Perko switch, only the battery it's switched to will charge when running. So, if you do have 2 different batts, you need to be sure that you recharge that starting batt before you switch it to the deep cycle - if you have the standard old style setup like I do.

There, clear as mud :)

Point is you can do it any way you want.
You will not hurt the altenator charging both batteries. I do it all the time.
Sometimes I run all day with the switch in the 1 or 2 position only, then next time I change to the other battery, next time in the both positon.
Again either way you won't hurt anything.

I also have an onboard hard wired trickle charger which I use if I won't be on the boat for a while. Still I've never had a problem with charging any of these 3 different ways.
Good Luck.
V.

>Are both batteries the same? If so, alternate between the 2 like >they said above. If one is a starting and the other a deep cycle - >then it's clear. BUT, I can tell you this: on MY Perko switch, only >the battery it's switched to will charge when running. So, if you >do have 2 different batts, you need to be sure that you >recharge that starting batt before you switch it to the deep >cycle - if you have the standard old style setup like I do.

My setup is Battery #1 is a starting battery- #2 is a deep cycle. I am almost positive that the alternator will only charge the battery you select.....not both, unless you go to ALL. Unfortunately, I believe the way mine is wired, ALL will put both batteries in parallel which is not good for charging. I will plan on alternating between #1 and #2 during my trips to keep both well charged - I always check them with a handheld voltmeter anyways.

Thanks for all the info!

Jim

This ought to be good....killed both batteries by leaving switch on ALL for a week.....So going to use booster/charger to start, on Battery 1, then switch to ALL when started, in hopes of charging both.... Guess I'll find out when I go to restart, with booster handy, tomorrow, if that gives a good charge to both.
I've been starting engine on Batt 1, then switching to all...the above sounds like this is not good practice. Having to rethink my engineering from comm fishing and offshore race boats. I thought I had two deep cycles when I bought the boat....

This ought to be good....killed both batteries by leaving switch on ALL for a week.....So going to use booster/charger to start, on Battery 1, then switch to ALL when started, in hopes of charging both.... Guess I'll find out when I go to restart, with booster handy, tomorrow, if that gives a good charge to both.
I've been starting engine on Batt 1, then switching to all...the above sounds like this is not good practice. Having to rethink my engineering from comm fishing and offshore race boats. I thought I had two deep cycles when I bought the boat....

Ross, when motor if off and you're running electronics or what have you, switch to #2. That way you know #1 is isolated and will be fresh if you need it.

Ross - NEVER EVER switch the battery switch when the motor is running!!!!!!

I have a 2 battery perko switch as well.... Battery 1 is motor and all electronics... for some reason when I switch to battery 2, it doesny power anything at all.... what am I missing here?

I have a 2 battery perko switch as well.... Battery 1 is motor and all electronics... for some reason when I switch to battery 2, it doesny power anything at all.... what am I missing here?


Not wired correctly....

Run on both and they stay charged...