Upgrading-is Class T needed

[Jwin60]

Looking for some guidance. I’m going to increase my truck camper battery capacity from two 12v AGM’s in parallel to 3 Li-time mini’s 12.8v/100ah, also in parallel (limited space to work with). It‘s stock camper wiring with a 30 amp service with a 30 amp fused/#10 awg directly from battery bussing to 12v fuse panel. There’s 340 watts of solar on the roof and an exterior solar port for my 130 watt portable. The update also includes a new MPPT controller. I previously installed a 300 watt inverter to charge an Ebike battery using #8 with a 40amp ANL fuse. I’ve searched but still confused on if I now need a class T fuse from battery to buss bar. It seems like the class t fuses are too large for my wiring. Any help is greatly appreciate.

 

[12VoltInstalls]

I’ve searched but still confused on if I now need a class T fuse from battery to buss bar. It seems like the class t fuses are too large for my wiring

Each individual battery needs a ClassT at the battery (+) terminal.

30 amp fused/#10 awg directly from battery bussing to 12v fuse panel

Inverter should not be fed from the 12v fuse panel but rather from the busbar imho.

previously installed a 300 watt inverter

Are you going to upgrade the inverter? 300W is ‘just barely’ and I’d speculate a 1200W would serve you better; I’d also run it through a GFCI

There’s 340 watts of solar on the roof and an exterior solar port for my 130 watt portable

…which is potentially 40A+ of charging depending on temperature etc.; I’d use 6ga from the mppt to the busbar and a 50A fuse (40A fuse minimum might blow now and again)

Having said all that, my recommendation would be to upgrade to a 1200 W inverter with the appropriate size cables and fuses and that way you can utilize that power for other things like a coffee maker, refrigerator, or that ebike, etc. But you would need to probably come up with another 300 W of solar panels imho.

 

[Jwin60]

Each individual battery needs a ClassT at the battery (+) terminal.

Inverter should not be fed from the 12v fuse panel but rather from the busbar imho.

Are you going to upgrade the inverter? 300W is ‘just barely’ and I’d speculate a 1200W would serve you better; I’d also run it through a GFCI

…which is potentially 40A+ of charging depending on temperature etc.; I’d use 6ga from the mppt to the busbar and a 50A fuse (40A fuse minimum might blow now and again)

Having said all that, my recommendation would be to upgrade to a 1200 W inverter with the appropriate size cables and fuses and that way you can utilize that power for other things like a coffee maker, refrigerator, or that ebike, etc. But you would need to probably come up with another 300 W of solar panels imho.

Thanks..