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vanchitect avatar image
vanchitect asked

Wire Guage & Fuse Size - Smart LiFePO4 Battery 25.6V/200AH Smart-a

Trying to determine the Fuse Size and Wire Gauge between a Victron 25.6V/200AH Smart-a Battery and a Lynx Distributor.

Should they match the Fuse and Wire specified by Victron for the connection of the Multiplus 24/300VA? Or should they be both be sized larger to accommodate loads in addition to the Multiplus?

I have searched and found varying/conflicting information online so I wanted to confirm.

battery-to-inverter-041723.jpg

wiringfuseswiring diagramlynx distributorbattery connection
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nesswill avatar image nesswill commented ·

good point to start

Wiring Unlimited (victronenergy.com)

Please ask after reading if you need anything else.

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kevgermany avatar image
kevgermany answered ·

Treat each run in isolation. Work out cable size and fuse size for each leg.

So multiplus to Lynx is multiplus max current - follow Victron's recommendation.

Battery to Lynx. Looks like you're missing a BMS. But. You need to work out and manage the current by installation design. Max charge current is multiplus max out. Plus any other chargers like solar. You give no indication of loads. So firstly you must work out all the loads at the Lynx. These must be managed so that you don't exceed the battery rating. Don't forget to include the Multiplus in inverter mode.

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vanchitect avatar image vanchitect commented ·

That diagram is just a piece of a larger system, which also has a VE.Bus BMS V2, Cerbo GX, MPPT Solar Charge Controller(s), Orion-Tr Smarts and an Orion DC-DC 24|12 Converter with it's associated 12v Loads.


The Total Load Current could be up to 132A and the Total Charge Current could be up to 225A; both values include a 125% safety factor. So, it seems like a 300A ANL Fuse and 2/0 Wire will work for the system as currently designed.

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