Author Topic: Charging batteries  (Read 4585 times)

Offline Djeffrey

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Charging batteries
« on: September 28, 2021, 06:19:42 PM »
I have a two battery system. One house battery and one starter, separated by a blue seas battery combiner. I have a xantrex charger and a xantrex monitor. If my battery’s get run down and I charge them by running the boat I get a 100% charge but if I plug the boat in at home I am not getting a full charge. Any ideas as to why? I am baffled

Offline TFreeburg

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Re: Charging batteries
« Reply #1 on: September 29, 2021, 08:28:09 AM »
I don’t know the answer, but I am learning a lot on YouTube from “Ask PYS”
It’s a channel run by an electrical engineer who specializes in boats.  He works out of Vancouver BC.  He sure knows his stuff.  I would bet he has already published an answer to your question.
Snohomish Tom
My goal: 25' Jumbo
First epoxy: 10/3/17
Flipped: 6/15/2019
Launched: 4/19/24

Offline KenB

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    • KenB Tolman website (done with iWeb)
Re: Charging batteries
« Reply #2 on: December 27, 2022, 10:46:02 AM »
Have you emailed or even better yet called xantrex?  1-800-670-0707
- Either this is how the charger is supposed to work and they will explain why... or maybe your unit is goofy. I completely agree this is not how what you purchased is supposed to work. And please post an update!


Semi-related, Professional Boat Builder published a "Task Sheet: Battery Combiner Installation (page 52, April/May 2021)" which left me more confused than before reading it:
- I was hoping to get an explanation on the merits of an ACR versus just a manual battery switch, plus some nuggets on wire gauge, etc. but instead it reads like an advertisement?
- My feelings are that the battery is so critical that I prefer to keep everything analogue... one deep cycle and one starting, with a simple battery selector switch. Everything but the engine fused at the rocker switches. When the engine is on, both batteries are always selected.
- If I turn off the engine but leave the fishfinder on or have the squid lights going, then I select just the house battery (e.g. isolate the starter battery). I have scared myself a few times by trying to start without switching back to both batteries (e.g. starting with just the deep cycle after it has been running without charging for a bit).
- No ACR for me... just the volt meter on the merc monitor. If I were to run high amps with the engine off for long periods, e.g. trolling motor or a sailboat, I might revisit the topic, but the benefits of simplicity outweigh the benefits of ACR, at least how I use my boat.

(PBB is great magazine! I look forward to every issue, so much good stuff in there... and I am not at all biased by the fact that my seacraft once appeared on its pages! On page 69 of Issue 78 - Aug-Sep 2000, all decked out for bluefin tuna:

- Bruce Armstrong   

"I can tell you that either a nice BFT or a big YFT is an absolute riot on a Tolman. The boat is so light it's like the old man and the sea..."
- Dave Nolan (RIP)