342 battery switch and battery charger wiring - 4 questions

dwmackenzie

I suspect my battery charger on my 2002 342 has bit the dust.  Had dead batteries.  Replaced all the batteries (they all were old and tested bad) but they still all drained down.  I think the cockpit fridge was causing the issue and the battery charger could not keep up. 

Question 1: Not sure why or how my house batteries could take down my starting batteries.  Any ideas?

I thought perhaps due to a bad battery isolator so I replaced that but when I pulled out the old one it tested fine (but for $120 and 30 min of my time I have that now ruled out).

So now I am looking to replace the charger (Intellipower PD 2040 - 40 amp unit) and bought a Pro Mariner Pro Nautic 1250 12 Volt 50 Amp 3 Bank Charger.  a bit more power... 50 amp instead of 40... plus Amazon delivered to my door the same day I ordered it!!  Everything I read says the chargers should be wired directly to each battery....not through a battery isolator as the current set up is.  In doing my research I could not find any Rinker wiring diagrams for how the batteries are wired to the battery switch.  The best I could find is the attached, which is an extract of an overall wiring diagram document that someone else posted but does not have what I am seeking.  It shows that the battery charger is wired to the battery isolator and the isolator is wired to the battery switches.

Question 2: does anyone have a wiring diagram for how things are wired from the battery switch to the batteries?

Question 3: If the attached diagram is correct, am I correct in assuming that while the battery switches are turned off, none of the batteries will charge from the battery charger?

Question 4: Any advice of if I should wire my new charger like the old one or should I go directly to the batteries, bypassing the isolator?

Dream_Inn

I installed the same charger a few years ago and did it thru the isolator.  Works perfectly.

Batteries will charge with switches off.  Only thing I did differently is use the temperature wire from the battery charger (that goes directly to battery).

LaRea

See my post in the other thread ... my isolator tested fine, but it was causing my charger to malfunction.  I bypassed the isolator, and now the charger works fine.  So I think the isolator is bad even though the multimeter says it's okay.  

My boat was wired as in the diagram:  alternators going through the isolator, battery charger connected direct to the batteries.  

LaRea

dwmackenzie said:

... Question 4: Any advice of if I should wire my new charger like the old one or should I go directly to the batteries, bypassing the isolator?

The isolator has two inputs (for the two alternators).  It has three outputs (for three battery banks).  Your charger has three outputs, and you connect them to the isolator's three outputs.  So, yes the charger outputs bypass the isolator, but the wires are attached to the isolator.  

LaRea

BTW I would not replace a 40-amp charger with a 50-amp charger.  [edit:  you're probably okay.  It's rated for a 15-amp AC circuit -- same as the original.]

LaRea

[edit:  you're probably okay.  It's rated for a 15-amp AC circuit -- same as the original.]

reneechris14

Question 3 you are correct the wires go from the isolator to the switch then the battery so you are right the fridge should not affect the start battery.

dwmackenzie

@LaRea, thanks for the replies and I saw your other post...strange.
@reneechris14 - I am hoping after installing new batteries, new isolator and a new charger that all my problems go away.....there is not much else to check.....unless somehow the battery switches are wired incorrectly.  I will keep you all posted once complete.

dwmackenzie

@Dream_Inn - I would be surprised if the batteries would not charge with the battery switches off but based on the wiring diagram it would appear that the circuit is interrupted.  I will trace the wires when putting in the new charger to sort this out.

LaRea

Today I replaced the isolator ... problem solved.  Here's the link with details:

http://rinkerboats.vanillacommunities.com/discussion/10106/installation-notes-promariner-proisocharge-battery-isolator

dwmackenzie

My update-I traced the wiring...on my 2002 342 I have 8 AWG wires (not 6 as us detailed in the wiring diagram that @Black_Diamond so kindly posted for a 2004 342) running from my charger to the output side of the isolator that then runs to the battery switches. I could not see but assume that these are wired to the same posts on the switches to which the battery connects. This then allows the batteries to be charged even when the switches are off. I do not know why Rinker would wire the chargers this way rather than directly to each battery bank. Any ideas?

So upon the discovery of the 8 AWG wiring this then meant I could not reuse these wires with the 50 amp charger I am installing (replacing my 40 amp Rinker installed charger)  . Turns out that even if I stayed with a 40 amp charger, that too calls for 6 AWG wiring which makes me wonder about Rinker’s use of 8 AWG on my 2002. Maybe that is why the 2004 now uses 6 AWG. 

So tonight I made all new cables with ring end connectors crimped on each end by yours truly. That was time consuming but easy. They will run directly from the charger to each of the three battery banks. So that is 3 wires plus a ground plus a chassis ground for a total of 5. Tomorrow I will finish the install and post pics. In the meantime here is a pic of the old unit and it’s replacement. 

It has been a fun project. Learning a lot which is half the fun. 

Dream_Inn

Very nice!  You will be extremely happy with the new charger.  

LaRea

Personally, I would not go direct to the batteries.  That would mean each battery has an input from the charger, an input from the isolator, and whatever outputs are already attached.  More connections means more risk of future confusion and mis-wiring.  

Rinker used #8 wire because the isolator is mounted next to the charger.  It's a short wiring run, so #8 is big enough.  Then you have bigger cables that run from the isolator to the batteries.

Dream_Inn

I agree with LaRea.  The only wire I have going directly to the batteries is the temperature sensing one.  The charger works very well in my setup and I now have all AGM batteries with the two house ones being the TPPL.  I get an extremely fast charge to my house TPPL batteries, which means a lot less time for the generator.