Advice on Existing Battery System Please

[APWTryfan]

Originally Posted by Pete7

If you fit 200w of solar you may not need a new AC charger if the existing one works, even if its a old single stage charger. Having fitted solar we rarely use the expensive mains charger now. However, adding a battery monitor (NASA BM1/Smart Gauge/Pro Mariner etc) would be good to see what is going with charging and discharging.

Pete

Hi Pete,

My solar controller came with an MT50 remote meter. Also the panels will come off during our harsh winters and batteries will be maintained by shore charger. I agree however, I will be very curious to accurately see the charging and battery status!

Andy

[APWTryfan]

Originally Posted by rbk

All charging to your house bank, the start battery uses very little ah when starting and the vsr will top it up quickly. If you run high loads off your start (windlass, thruster) you may want to switch to an arc for higher charge capacities (assuming your current vsr is around 15amp or so?) A second back up start battery is ridiculous imo and if you wanted more capacity make it a 3 battery house bank.

Sorry I did not mean a 2nd backup starter battery.

2 x house AGM and 1 x start battery. Would you charge AGM only by solar or could they be charged by alternator?

Thanks again I really appreciate all the help and feedback on this forum!

Andy

[rbk]

Originally Posted by APWTryfan

Sorry I did not mean a 2nd backup starter battery.

2 x house AGM and 1 x start battery. Would you charge AGM only by solar or could they be charged by alternator?

Thanks again I really appreciate all the help and feedback on this forum!

Andy

Run the shore charger, solar and alternator all to the house bank. The VSR will charge the start as the house is charged. The house will be fully charged in a matter of minuets (assuming a healthy and full start battery upon engine start) then your charging systems can go about charging your much more extensively used house bank. Like I said before you'll probably have to go with an AGM start battery as well as the charging profiles for the house bank (AGM's) will carry over with the VSR (could cook a FLA with the AGM charge profile; These profiles will come from your shore charger, Alt. regulator and MPPT). You could buy a new dc2dc combiner (like the Balmar Digital Duo) then you can mix and match batteries, ARC's and VSR's not so much.

[rbk]

Read this and see below diagram. Essentially all charging is direclty wired to the house via a common bus to keep stacking the battery terminals down and makes for a cleaner setup. The added battery switch allow bank isolation.

https://marinehowto.com/automatic-charging-relays/

[APWTryfan]

Originally Posted by rbk

Read this and see below diagram. Essentially all charging is directly wired to the house via a common bus to keep stacking the battery terminals down and makes for a cleaner setup. The added battery switch allow bank isolation.

https://marinehowto.com/automatic-charging-relays/

Ha Ha - I'm in the process of reading. Not exactly a light read but I'm getting through it! I am trying to minimize impact with this project and would like to keep the existing Off-1-All-2 switch (1 for start and 2 for house) to distribute loads. Also the Xantrex Pathfinder VSR I have is probably a few decades and would consider modernizing with Blue Sea ACR. I could also consider an echo charger not sure what would be better.

Once again I really appreciate all your help!

Do you sail in YT? I'm in Comox, BC.

Andy

[rbk]

I think the echo can charge mixed chemistry batteries but not 100% sure. I know the Duo does for sure. The ARC is nice if you run high load stuff off your start (thruster windlass) as they can handle higher loads. We keep our big boat in south east Alaska but I do sail my smaller boats in the Yukon. I was born in Comox.

[APWTryfan]

Originally Posted by rbk

I think the echo can charge mixed chemistry batteries but not 100% sure. I know the Duo does for sure. The ARC is nice if you run high load stuff off your start (thruster windlass) as they can handle higher loads. We keep our big boat in south east Alaska but I do sail my smaller boats in the Yukon. I was born in Comox.

Nice!

OK I'll leave it at that for now - you have been very helpful and I really appreciate it!

Regards,

Andy

[APWTryfan]

Originally Posted by rbk

I think the echo can charge mixed chemistry batteries but not 100% sure. I know the Duo does for sure. The ARC is nice if you run high load stuff off your start (thruster windlass) as they can handle higher loads. We keep our big boat in south east Alaska but I do sail my smaller boats in the Yukon. I was born in Comox.

Good morning Mark (I got your name from your profile).

I'm putting together my wiring diagram and struggling to understand the alternator / starter wiring configuration. As far as I can tell the current configuration (2GM20) is such that starter/alternator are connected to the common post on the Off-1-All-2 switch with a single wire.

With my proposed configuration (rev 1, attached) would I still connect starter/alternator to common post?

Thanks!

Andy

[rbk]

I would run your alt to your common + bus and not through the stater. Depending on your alt and regulator and how anal you are about correct voltage charging and compensation, there should be as few connections between charging sources and your batteries more so if your regulator isn’t compensating for it. The problem with running the alt through the switch is if you (more likely a guest) accidentally switches your 1/2/b to the off position you’ll fry your alt.

[APWTryfan]

Originally Posted by rbk

I would run your alt to your common + bus and not through the stater. Depending on your alt and regulator and how anal you are about correct voltage charging and compensation, there should be as few connections between charging sources and your batteries more so if your regulator isn’t compensating for it. The problem with running the alt through the switch is if you (more likely a guest) accidentally switches your 1/2/b to the off position you’ll fry your alt.

Thank you,

The alt/starter on my C&C33 are really difficult to get too - I'll have another look, but I'm not too keen on rewiring. The current configuration is such that alt/starter are wired to common post on switch so at least I know that works (albeit risky as you had indicated).

I've attached an updated configuration.

Regards,

Andy