Another solar panel install question

[Juice6576]

When tying in the battery connections to the MPPT Controller outputs, do I have to go to the battery posts? Can I tie in to the battery connections on the DC Panel like the battery charger does? I would still use an inline fuse holder at the connection.

 

[Davidasailor26]

It all depends on wire sizes. If the wire gauge from the DC panel to the batteries is large enough to carry the charge current without significant voltage loss then it should be fine. If the wire from the batteries to the panel is fused with a fuse too large for the MPPT wire then you should still add the inline fuse to protect the wire between the DC panel and the MPPT.

 

[DArcy]

My solar MPPT is connected to a battery bus bar, not directly to the battery. The fuse between the battery and bus bar is 200A so I also have a 50A fuse between the MPPT (30A rating) and the bus bar. The bus bar ties in the solar MPPT, DC switch, both battery charges, alternator, always on circuits and the ACR to charge the start battery.

 

[Juice6576]

That's what I thought. Just wanted to bounce that off with you guys. Thanks

 

[Juice6576]

So I decided to run just the charging current to the house battery as my boat already has a combiner relay that will charge the start battery if it's voltage is lower than the house battery. I connected the MPPT Controller to the battery fuse. I have a 40A inline fuse in the lead.

 

[jssailem]

Sounds sensible. How is it working?
I am left to assume that the wires are capable of handling a 40amp DC load.

 

[Juice6576]

Sounds sensible. How is it working?
I am left to assume that the wires are capable of handling a 40amp DC load.

Yes, the controller wire is AWG 8 with a short run of 4 feet. The lead to the battery bank is rated for 200A