This is for an Island Packet 380 sailboat. It’s currently outfitted with 3x AGM’s for the house, and 2x AGM’s for the windlass/thruster.
Everything is 12v.
Here’s the system I’ve been sketching out:
House battery: 4P4S EVE LF304Ah LFP cells
Windlass/thruster battery: 1P4S EVE LF304Ah LFP cells
House and windlass batteries to be joined by an interconnect conductor 6m (20’) (one way) of 8 or 6AWG
With appropriate breakers at batteries at each end - 60-75A for 8awg or 100A for 6awg (correct?)
- Though I might up the size to support 150A for the windlass at least, to have a backup for that.
The rated output of the EVE LF304Ah cells is 2C for ~30sec
1P4S should be ok for thruster’s 680A max load especially if supplemented with house bank via interconnect
(I'll measure actual Amps with a clamp meter when I have an opportunity)
Windlass is a Simpson Lawrence (Amperage TBD, but probably roughly <150A)
Advantages of this dual-bank configuration:
Sources:
Bonus if one or more charging sources can be branched separately to both banks to equalize independently if necessary.
There exists potential for conflict if paralleled charging circuits bypass interconnect, thus, branched and isolated bank charging is preferred.
(Is there an alternator that can charge dual banks?)
Anything in this seem off?
Sounds like a great idea?
This is a work in progress so I really appreciate feedback on this design idea.
Thanks!
Everything is 12v.
Here’s the system I’ve been sketching out:
House battery: 4P4S EVE LF304Ah LFP cells
Windlass/thruster battery: 1P4S EVE LF304Ah LFP cells
House and windlass batteries to be joined by an interconnect conductor 6m (20’) (one way) of 8 or 6AWG
With appropriate breakers at batteries at each end - 60-75A for 8awg or 100A for 6awg (correct?)
- Though I might up the size to support 150A for the windlass at least, to have a backup for that.
The rated output of the EVE LF304Ah cells is 2C for ~30sec
1P4S should be ok for thruster’s 680A max load especially if supplemented with house bank via interconnect
(I'll measure actual Amps with a clamp meter when I have an opportunity)
Windlass is a Simpson Lawrence (Amperage TBD, but probably roughly <150A)
Advantages of this dual-bank configuration:
- Conforms to ABYC requirement for redundant backup bank
- House bank can be taken offline for servicing during which time the windlass battery will provide operating power at only marginally reduced capacity
- Supplemental thruster load sharing from the house bank
- Selection via OFF-1-2-BOTH battery switch to the house load
- Adding a simple LED digital mili-voltmeter between the bank positives to determine that it’s ok to parallel
- And a length of resistance wire to manually equalize banks if necessary
Sources:
- Upgraded alternator on the Yanmar diesel
- Shore power / genset 110v charging
- Solar (eventually)
Bonus if one or more charging sources can be branched separately to both banks to equalize independently if necessary.
There exists potential for conflict if paralleled charging circuits bypass interconnect, thus, branched and isolated bank charging is preferred.
(Is there an alternator that can charge dual banks?)
Anything in this seem off?
Sounds like a great idea?
This is a work in progress so I really appreciate feedback on this design idea.
Thanks!
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