Battery Charging / Combiners

[Barry7363]

I am interested in upgrading the electrical charging & switching system on our recently acquired Catalina 34. The previous owner(s) added a separate start battery, together with two "house" deep cycle batteries, all are group 27 size, wet cell. The switching arrangement is, at best awkward, and somewhat strange in that there are two conventional 1-both-2-off switches, with the main panel switch controlling the start battery. I am contemplating replacing the two existing switches with a single e-series Battery Switch Dual Circuit Plus, and a 7610-SI-Series ACR, (Blue Sea System "Add-a-Battery". My quandry is understanding how I can set it up to accept shore power charging (through the on-board 35 amp AC charger) when at the marina, as well as from the engine alternator while underway, to both the house and engine batteries. I cannot find a wiring diagram in the manufacturer's literature that clearly addresses the above scenario. Does anyone know if the "Add-a-Battery" work with what I describe above? If so, how should it be wired?

Guidance in solving this problem will be much appreciated.

Best Regards,

Barry White
Eastern Passage, Nova Scotia,
Canada

 

[sailingdog]

The BlueSea DCP is an excellent battery switch, and using it with the ACR is a good solution. The alternator output wire should be connected to the house battery bank directly, as should the AC charger. Then when either is charging the house bank, which sees much more of a load than the starting battery, the ACR will combine the two banks to top off the starting bank.

A slightly better solution would be to get an echo charger and use that in place of the battery combiner.

 

[Dave Groshong]

Blue Seas ACR available on this site:

http://shop.SailboatOwners.com/detail.htm?fno=400&group=1000&cat=3319

Lower price than Defender

 

[Don12364]

Blue Seas ACR ???

I bought one - full of expectations. Wired it in, connected charger and observed operation. We needed to depart before the batteries were fully charged and I was astounded to see the ACR was still connecting both house and engine batteries when the charger was off. Had I thought it through I would have realised this was bound to happen.
The relay had come in when the shore power charger was first connected and would remain connected until both batteries were down to 12.5 volts. Then I noted that, in the energised state the ACR was drawing 0.2 amps - and would continue to do so until it had discharged both batteries to 12.5 v whence it would open.
To me 12.5 v represents a state of charge well below full charge and, as the whole unit is potted with no access to adjust this opening voltage, I reverted to my original combiner system which has no current draw as soon as the charger goes off (the combiner is fed from a 12v separate power brick from an old rechargeable torch and this is fed directly from the incoming mains shore supply).
Now the ACR sits on my garage shelf gathering dust.
Useless.

 

[Dave Groshong]

Re: Blue Seas ACR ???

Wow Donalex, I'm surprised because I've heard such great things about this Blue Seas combiner! Where did you purchase it? You should be able to get a refund, Blue Seas is pretty good in that regard.

 

[ITMaster]

Maybe Donalex

Now the ACR sits on my garage shelf gathering dust. Useless.

You could sell it to Barry since you aren't getting your full value of the cost of it.

If I didn't like it and someone wanted one, I would see a chance to get a portion of my money back. :cry:

 

[Stu Jackson]

Welcome to the 'site, Barry

Your question is a good one, and there are a number of different ways to do this. I'll take a look at it and respond in detail later in the week, or to you directly with some earlier articles and links from our C34 'site. Many of us are active on both boards.

With your new-to-you Catalina 34, you may want to also join us over at www.c34ia.org, and check out the Forums / Message Board, similar to this board, and specific to your Catalina 34.

Send me a personal message and I'll email a wiring diagram of how we've done ours as starters for you.

You can use one of the 1-2-B switches you already have WITHOUT spending $$ on the new switch and the ACR and make it work.

 

[Barry7363]

Gentlemen, Thanks for the feedback. I obviously have some reservations with the Blue Sea System equipment (given the response from Donalex, which was much appreciated) and have considered the possibility of simply using the primary existing switch in a "rational" manner. Stu, I have registered on the C-34 site, but as yet haven't taken an annual membership. (Too many other activities going on at this point). However, I am interested in hearing the specifics of how you've wired yours.

Cheers,

Barry

 

[sailingdog]

Barry-

Would highly recommend you not post your e-mail address in machine readable form, unless you like spam.

 

[Barry7363]

Re e-mail post

Saildog, Good point, thanks for that, (now how can I "unring the bell"?)

Barry

 

[sailingdog]

Maine-

Can you remove the mailto: HTML link on his address. That's just as bad as having it machine readable.

 

[Barry7363]

Thank You Mainesail for your prompt response in removing my personal e-mail link from exposure... As I understand it, it has been rectified?
Best regards,
Barry
(BTW, I have enjoyed your technical articles and found them enlightening in resolving an number of maintenance issues).

 

[Stu Jackson]

In addition to the material I sent to you

the short answer to your question is that the charging sources should go directly to your house bank, including the shorepower charger, the alternator and any other inputs. Once you decide what to do about switching, you'll figure out how to combine the emergency reserve (or start) bank, there are many options, the easiest one is an echo charger (or a combiner, which you can turn off with, you guessed it, another switch - but only needs a simple toggle switch on the ground wire).

 

[Stu Jackson]

ACR settings

This is from the Blue Seas website for the ACR:

When the sensed voltage is below the COMBINED voltage level (default setting of 13.5 volts), the relay is open. The batteries are not connected and all electrical loads are on one battery while the second battery bank is isolated. When the sensed voltage is 13.5 volts and has remained at that level for at least 30 seconds, the batteries are combined together. When combined, both battery banks are charged. When the sensed voltage drops below the UNDERVOLTAGE level (default setting of 12.7 volts) for 60 seconds, the relay opens. The house battery bank is not being charged. If the house battery bank is being discharged through loads connected to it, the start battery bank is isolated and will retain its charge.

Seems the scutoff voltage is 12.7, not 12.5. That would make a difference, but I would set it, if adjustable, at 12.8 V, like the combiner does.

The larger drawback to the ACr is the current - 60 A, which would make it difficult with a large high output alternator for a dead start bank. If the start bank doesn't get depeleted, it'd seem to be fine.

 

[alexco38]

Re: ACR settings

Thats why the Echocharger is a better solution. It limits the current going to the start bank. And besides why would the start batttery be discharged so much that you need 60A to bring it back alive. If you totally discharged the house bank, its time to start the engine to charge them back. Never combine the start to house bank unless you like to crank start the motor.

 

[sailingdog]

The larger drawback to the ACr is the current - 60 A, which would make it difficult with a large high output alternator for a dead start bank. If the start bank doesn't get depeleted, it'd seem to be fine.

It depends on which model ACR you have. The oldest, which is the CL-series long rectangular one, is rated for 60 Amps, the smaller squarish SI-Series is rated for 120 Amps... and ML and L series are rated for 500 and 450 Amps respectively...

 

[sailaway78]

Check your charger first

I would recommend that you check your charger output before you start buying new parts and pieces. Many chargers have an output for tow seperate battery banks. Usually with a smaller output to the start battery. If your charger has a two bank output, you will need to rethink your current plans. I would also recommend looking into an echo charger or an isolator. Simpler is always better.