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Electrical Refit Sanity Check

Br3nt

.
May 14, 2011
23
C&C 39 San Francisco
Ok, I realize 'refit' and 'sanity' don't belong in the same thread. Anyway, among the refit we're doing on our C&C 39 is a long overdue gut of the 40+ year old electrical systems. I know the residential breakers in the cockpit locker still technically work but we just decided it was time. I've been working on what we want based some on what we have - which is most of the major components in the diagram.

Admittedly I've gone to 6AWG when 8AWG would work in some places as for some reason my tools only crimp either larger or smaller than 8 but not 8. Great planning on my part I know.

Any thoughts or feedback? I generally know what I'm doing but I don't do it frequently enough where I think I'll catch everything.

Shillelagh v2-Core Power (3).png
 
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Jan 11, 2014
7,826
Sabre 362 113 Fair Haven, NY
Why the 60A GI when a 30A GI would be appropriate and cheaper?

@mermike Had the same question at first, I believe it is a charger.
 
Jan 11, 2014
7,826
Sabre 362 113 Fair Haven, NY
Ack, I didn't label that. It's a blue seas 40a charger. I'll see if I can update it.
=View attachment 188176
If you are using Firefly batteries you'll be better off with a larger charger. Firefly recommends charging at .4C with a minimum of 25amps per battery. The most your charger will do is 20 amps per battery. Each Firefly is rated at 116 ah, you'll have a total of 232 ah. They will easily handle up to 60 amps of charging.
 

Br3nt

.
May 14, 2011
23
C&C 39 San Francisco
If you are using Firefly batteries you'll be better off with a larger charger. Firefly recommends charging at .4C with a minimum of 25amps per battery. The most your charger will do is 20 amps per battery. Each Firefly is rated at 116 ah, you'll have a total of 232 ah. They will easily handle up to 60 amps of charging.
Good catch, it's not optimal but I have it already and I like the way it works with the ACR to isolate the start battery. I'll probably update it in the future and if all my plans work out add additional FF batteries.
 
Nov 21, 2012
281
Yamaha 33 Port Ludlow, WA
You've got a galvanic isolator, do you have an AC system on board?
 

CarlN

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Jan 4, 2009
577
Ketch 55 Bristol, RI
While Firefly batteries are pretty tolerant, I wouldn't have a charge rate below their recommended rate. Just add a 2nd charger and turn it on when the batteries are quite discharged. Charging is something you want redundancy for anyways. You don't need to do anything special or wire it into the ACR. As the batteries get close to full, one will tend to go to float first and effectively turn itself off. Be sure you wire your two Fireflys so that the positive feed cable goes to one battery and the negative feed to the other battery. This makes them charge and discharge in a more balanced way. And for your cables, I've been using GenuineDealz for 10 years for all my larger gauge battery cables. His prices and quality of wire is great and he'll make up custom cables to the inch for about $5 a cable plus the materials. His crimps are far better than you'll ever do - or even your boatyard. They really are a work of art. Also, if you look on his site under "Help" he has a wonderful voltage drop calculator. Genuine Dealz
 
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