Cal 36 Power System Refresh

[gearboxlabs]

Hi all,

I'm currently in the process of designing and building out my new power system on my 1966 Cal 36 sloop. I'm looking for any feedback y'all might have on how I may be "doing it wrong" with the following design, and am interested in discussing the approaches available.

The legacy power system is .. challenging. It features 8D flooded batteries, a Heart Freedom 10 inverter/charger, and a bunch of legacy crap that I don't love. Including that the old batteries are in the way of getting to the aft end of the diesel engine. It's tough to understand the state of things in that system, and I don't trust it. Quite the bummer there.

But all that is the old way, and I'm working on designing out a new system that makes better use of modern systems, adds solar, and generally is easier to maintain and understand.

This new design separates the house system from the engine system more.

Batteries​

• Starter battery is a flooded lead acid battery from the auto parts store, around 80Ah capacity
• House battery is a DIY 280Ah / 12V setup made with Eve cells, and an Overkill BMS for cell management
• Battery management is handled through a Victron BMV 712

Charging sources​

• Shore power connects to the Victron MultiPlus 2000VA, providing charge to both the house and starter battery
• Solar power via two 200W 24V panels connects to the Victron MPPT 100/30, providing charge to the house battery only
• Engine Alternator connects to the starter battery, and that can charge the house system through an Orion Tr 12-12 18A to limit risk to existing alternator/controller. A lead-acid starting battery is being used in the starter system to provide the cranking amps for the starter, and to not have to re-engineer the whole engine system.

Power System Loads​

• MultiPlus to provide AC outputs from shore power or through its inverter
• Various legacy boat systems through the DC panel (chart plotter, depth sounder, autopilot, etc)
• Anchor Windlass (70A breaker) -- second largest load

Known Risks​

• OverkillBMS is limited to 120A discharge, which is less than the MultiPlus could pull since it's a 2000VA inverter (max=156A)
• Solar currently doesn't have facility to charge the starter system, although in a pinch that could be reconfigured from the starter --> house Orion.

Thoughts? Feedback? Thanks in advance.

 

[Wibla]

OverkillBMS is limited to 120A discharge, which is less than the MultiPlus could pull since it's a 2000VA inverter (max=156A)

Check the Multiplus manual, you might be able to limit it in the settings.

I would add on/off battery switches to both batteries + link the positive busbars with a separate battery switch, so you can operate the whole system from either battery (in a pinch).

I'm lazy, black circles = switches

 

[gearboxlabs]

Thanks for the feedback. I definitely planned to examine the manual for seeing if I can current-limit the inverter. And thanks for catching my cut'n'paste fail.