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Chris avatar image
Chris asked

Please critique my proposed setup. Large schematic ahead... Cerbo GX, Touch 70, Smart Battery Protect 220, Lynx BMS, Lynx Distributor x 2, Quattro, Orion-Tr x 4, Smart100/50 x 5, Lithium 330ah x 3,

I used this schematic for inspiration: https://www.victronenergy.com/upload/documents/MultiPlus-3KW-120VAC-12VDC-600Ah-Li-Lynx-Smart-BMS-&-distributors-Cerbo-GX-touch-generator-MPPT-Orion-Tr-Smarts.pdf

Here is the PDF 2008 Leopard 40 SV COSMOS Electrical & Solar Upgrade 2021 (1).pdf

Boat is a 12m sailing catamaran with two engines. One alternator per engine. Ripping out current system of LG NeonR 360wp x 4 PV, 900ah Firefly Oasis AGM, Xantrex RV2012GS Inverter/Charger.

I have intentionally wired the alternators on circuits without a On/Off switch. Alternators wired directly to the starter batteries. Starter motors are wired through On/Off switches.

Lynx BMS shows ATC wire going to ignition. How do I handle for two engine setup? Is this needed? Do I wire to one or both?

Can I double stack MRBF on a single battery post?

Please critique the setup and tell me your thoughts. Is there a better way, simpler way, cheaper way, easier to install way?

I currently have a BMV-712 installed with temp sensor. It appears this function gets replaced by the Lynx BMS. I also have a spare BMV-712 new in the box. I was thinking about hooking them up to each engine start battery. My DC panel has a rotary switch and old analog voltage gauge for the start batteries. I plan to leave this installed as well. So the BMV-712's would be redundant. This is my first electrical drawing. Used Canva.com which we use for website stuff already.2008-leopard-40-sv-cosmos-electrical-solar-upgrade.jpg

system designschematics
2008-leopard-40-sv-cosmos-electrical-solar-upgrade.jpg (4.1 MiB)
2008-leopard-40-sv-cosmos-electrical-solar-upgrade.pdf (11.3 MiB)
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3 Answers
hjohnson avatar image
hjohnson answered ·

If I was you, I’d look at getting those alternators modified to use an external regulator (if they’re not so modified already) and then a pair of Wakespeed WS500 external regulators to control them. The wakespeeds will communicate both with each other, to split the charging equally, and with the Victron setup so that they don’t trigger a battery disconnect. They also monitor the alternator temperature so that they don’t overstress the alternators. This will let you push 200+A into your batteries from the engines if you need/want to.

Because they’re integrated, they will also tail off/shut down gracefully as your battery hits maximum charge, preventing the BMS from triggering a battery disconnect in a high voltage situation.


I would then use the Orion-TRs to keep your starting batteries maintained. You can also drop your starting batteries down to little 50Ah starting batteries, reducing your costs, weight, and space.

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Chris avatar image Chris commented ·
Thank you for your response. The alternators are brand new Valeo 125amp. I definitely don't want to replace them, but might be willing to modify them. Other than faster charging potential, the Lynx BMS and Orion should have all the same benefits you mention.
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Chris avatar image
Chris answered ·

https://tinyurl.com/yp23k4uk

New and updated PDF.

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Charles Gomes avatar image
Charles Gomes answered ·

I've a similar setup with 5 LG400Watts on a truck instead of a boat. I'm wondering why did you decide to go with 5 controllers instead of a single one ? Is that because of shading ? Shouldn't shading problem be eliminated by the panel bypass diodes ?

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