Battery advice

[BiXLL]

I have posted this question other places, and I appoligize if I am coming accross as redundant, but I am not getting any help. Please advise if you can.<br /><br />OK, I thought I had it all figured out, but now that my Perko switch is here, I am more confused then ever! The boat came from mfg with 1 battery. The dealer took everything away from the cranking battery except the motor, and installed a deep cycle battery for all accesories. I have the 2 Heavy wires (black and red) running to the cranking battery. I have 4 thin wires running to each terminal on the deep cycle battery including charger wires. The only way to charge the deep cycle at present is with the on board charger. My goal is to keep the batteries seperate, but I would like to be able switch them together when underway so as to be able to charge the deep cycle, or run my lights, ect if I should drain the deep cycle durring the day.<br />After sitting there looking at it for a while, I am wondering if this will work. Run a cable off the + cranking battery to position 1 on the switch. Run cable from + deep cycle to position 2 on the switch. Leave switch in off position untill underway and switch to all position to charge deep cycle. Would that work? Would I need to run the ground sides of both batteries to the ground pole of the switch? Is there a better way of accomplishing this?

 

[Boatist]

Re: Battery advice

BiXLL<br />As you posted it will not work. You would not be able to start motor with switch in the off postion. Also if you did start it and and switch to off you will blow up your alternator unless your switch has field disconnect circuit.<br /><br />To start with run both negitive battery wires to engine block or connect your deep cycle negitive to your starting negitive and leave the starting negitive hooked up as is.<br /><br />Not knowing if you have a I/O or outboard can only give you basic wireing. The normal starting battery + red wire should go to terminal 1 on your switch. The common wire on the switch should run to where your starting battery + red wire was connected before, (starting solenoid). The + red wire from your deep should go to terminal 2 on the switch. That is the basic wireing.<br /><br />I do not know which switch you have but there many types. Some if you turn the switch with the motor running you will blow your alternator diodes. So if you want to charge both batteries thru the switch turn the motor off with the key. Turn the switch to both or all then start your motor normal. Do not turn the switch with the motor running. <br />There are switches that are called make before break and with this type switch you can safely turn with the motor running but if your turn thru off you will still blow your alternator output diodes.<br />Another type switch has a field disconnect circuit and it requires more wireing but once hooked up you can safely turn the switch and not hurt the alternator.<br />One last thing if you dock your boat and when leaving you turn to off postion remember every thing will be off even any automotic bilge pumps unless they are wired direct to the battery.<br />Good Luck

 

[18rabbit]

Re: Battery advice

My concern is your mention of leaving the switch in the “off” position until underway. Normally, after you have started the engine you do not disconnect the battery or turn the switch to the “off” position unless your alternator’s diodes are protected for this.<br /><br />EDIT: I believe the Perko switch has the “Both” position between the “1” and the “2” positions. After starting the engine, you should not switch to the “Off” position. But you can switch from “1” (starting bat) to “Both” … and even over to “2” (deep) without a problem.

 

[bubbakat]

Re: Battery advice

I'll have to look at the papers first to see, but I do believe perko states on the instructions not to switch to all position while motor is running

 

[BiXLL]

Re: Battery advice

Thanks fellas, I have it figured out now. On the switch, the poles are marked 1,2, and common. I was thinking common meant ground! After this boneheaded truck driver was shown a diagram, he realized common is the starter/alternator lead! It was like somebody turned the light on for me! It all makes sense now!

 

[ThomWV]

Re: Battery advice

Bill.<br /><br />Think of that "Common" as the output lug and the other two lugs as where the switch gets its input from the batterys.<br /><br />I personally think that using a separate "starting" battery devoted to the engine and then a second battery to run the house loads is the worst possible way to hook up the batterys in a boat that sees day use - but there are tens of thousands of them out there wired that way. I won't do it for folks myself, if they want to hire someone to wire their boats that way they can hire someone else. Tnis is the way I prefer to do it for a day boat:<br /><br />

 

[JB]

Re: Battery advice

Moving to Boats<br /><br />Please read the header for this forum.