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saberg's avatar
saberg
Explorer
May 28, 2018

Battery and Converter/Charger Upgrade and Fuses

Hello all! First post and I am trying to get the hang of it.

I am beginning a project to upgrade one 12volt house battery to 2 6volt batteries. Included in the project will be a PD9260 charger and a Victron monitor. Also, I will be placing the charger close to the batteries.

I am working with a 2011 Forest River Sunseeker 2860 Class C. The current charger is under the rear bed next to the AC/DC distribution panel WFFCO 8930, and the battery is under the entry step. Here is a close diagram of the current wiring. It's for a Sunseeker 2300.



I could use some help with the fuses. All battery and charger wire is #2. The plan is to put a 200A MRBF on the pos battery post and connect that to a MRBF fuse block. Then put a 100A MRBF on the pos going to the charger.

I would like to protect the #6 wire going from the BCC to the distribution panel and it looks like there is a place to place a fuse in the BCC.

This is the back of the BCC.



And the front.




This is where I get pretty lost. It's hard to see, but there is a brass and a silver post side by side with wording above that says MAX 50A Breaker. What is supposed to go there? Forest River has not been responsive.




What about putting a 50A MRBF on the stud on the back of the BCC where the distribution panel wire connects? That is the top stud of the 3 that have wire connected.

I sure could use some help. Thanks.

10 Replies

  • there is already a self resetting breaker on the other side of the circuit board


    Oh that's interesting and would be nice. I guess I will need to get behind that circuit board and check it out.
  • enblethen wrote:
    I would also be careful about tieing chassis and coach system together without an automatic system such as a relay to separate them. You could end up with all batteries being dead.


    The OP second photo at the bottom shows what looks like the isolator in my MH which is mounted up front near the engine battery. It is open unless ignition is on when it closes, allowing "alternator charging". It does not work in reverse so you get converter charging of the engine battery when the engine is not running. For that you need to do something else (another topic).

    In this case it seems to be all at the "BCC", which is near the house battery box by the steps, but this is not the WFCO "power centre" for the house. You can change the converter from the WFCO, but that still leaves the original power centre with its DC fuse panel up in the bedroom at the back.

    The OP says Victron monitor, but has no provision for it in the drawing--such as its shunt.
  • The diagram with the 2 batts is not mine, just a good trace of the wire. I only have 1 12volt batt currently. Thanks for the info on the 2 batt wiring.

    Thanks BFL13 for the info on the shunt wiring.

    enblethen, I was wondering about the genset wiring, thanks for that. I have tried to find info on that circuit board. In the bottom left corner it says manufactured by EXCEL electronics excelelectronicsinc.com, made in the USA, Forest River Inc. There is also a white sticker on the top left of the board that has EEI1027730T 026-005 1065 Sim - 1. I'm sure that means something to those guys but I did not have much luck getting information from them. The BCC contains a BIRD for chassis/house.

    Still not sure why the board would specify a breaker. There is also wording related to a mini ANL fuse.
  • I would also be careful about tieing chassis and coach system together without an automatic system such as a relay to separate them. You could end up with all batteries being dead.
  • mike-s wrote:
    You want the 2x 6V batteries in series, you have them wired in parallel in the drawing.

    With two 6V batteries, series mean positive (+) to negative (-). The other positive and negative feed your "load". In your case negative (-) goes to chassis ground and positive to terminal A with the feed to the genset starter.
  • Your fusing needs to protect the wire.
    The fuse should be the same or smaller rating then the converter. 60 amp fuse would be good.
    The genset could go directly to the battery lead and not go through a fuse.
    The two bolts marked fifty amp looks to mount a fuse. verify spacing.
    Look for some identification on the fuse panel and post it. I cannot read information in lower left corner of third photo.
  • You want the 2x 6V batteries in series, you have them wired in parallel in the drawing. Or is it that you currently have 2x 12V ones?
  • You need to place the monitor's shunt so all the negs go to it first, then the single fat wire from the shunt to the neg batt post. That includes the neg now going from the house batt to the frame. If comes off the neg batt post and goes now to the outer end of the shunt.

    Are the power centres getting confused here which is for what? A friend has a Sunseeker where the converter is on the back pass through front wall, connected to the power centre inside on back of that wall by the bed. ISTR some other power stuff was down there by the steps in an outside compartment. Your have alternator charging to the house batts through that one, not to be confused with converter charging via the other one.

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