We are in the middle of a refit for the electrical system of our fiberglass sailboat so we can be off the grid as much as possible this summer. We've installed a new non-victron 300ah lifepo4 battery, Orion (connection between starter and lithium for charging with alternator), Smart Shunt, Cerbo Gx, Multiplus 3000, 3 mppt's and a Lynx distributor for connecting everything.
The grounding point we will connect the Lynx to is a single m8 bolt mounted on a bulkhead, which currently has a flat mesh braid that connects to the engine, and a 2nd smaller insulated copper (bundled) wire (unsure of size but no larger than 35mm2) that connects to the through hull, with exposed wires clamped on to the metal via a hose clamp.
The Multiplus is connected to the Lynx distributor via 4 50mm ( +/-) cables.
Q1) Does the Multiplus need to have a dedicated grounding wire from the multiplus case? Can this be connected to the Lynx or must it go to the existing grounding point?
Q2) In either case what size cable is sufficient to ground the multiplus with 50mm2 cabling connection to the lynx and 70mm2 battery cables?
We have 35mm2 cable spare, would that be sufficient? Or is 50mm2 the only option? (it would be a difficult run for the cable that size is why I ask but needs/must) The run from the lynx to the grounding point is about a meter, it's 2.5 meters for the multiplus to the direct ground.
Q3) is a single grounding point sufficient?
Q4) What is the function of that insulated wire clamped to the through hull, since the shaft *should* serve as a grounding point (iirc)? And if it does serve a purpose, shouldn't we enlarge that cable to match the other ground cables?
Thank you! ⚡
