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What fuse and breaker bar ratings to use in our electrical wiring?

Most of my wiring is from TEMCo. It's been good for me. I would buy from them again. The only downside was that they put a large amount of cable in a single box and it was very heavy. My mailman is probably still cussing me out.
 
MRBF (Marine Rated Battery Fuse), not MBRF.

There is usually a battery disconnect in this leg:
+ Battery --- (2/0 AWG) --- 150 A fuse --- (2/0 AWG) --- Switch --- + bus bar
The recommended fuse is a Class T on this leg, not MRBF. Elsewhere MRBF is OK, but many are using circuit breakers on the cable to the inverter.

A warning on using MRBF:


This is a really old doc on MBRF - 2007. I've not seen a fuse terminal like that being sold in years but do run into them in use on occasion and remove them and replace with the modern variety. The modern variety allows a couple lugs to be mounted as the stud is now on the "fused" side and the isolation bushing is in the terminal base.

Also note these terminal blocks will cost $35 or so from Bluesea but can be had from waytech for under $15




41XG1Bdo5DL._AC_.jpg
 
This is a really old doc on MBRF - 2007. I've not seen a fuse terminal like that being sold in years but do run into them in use on occasion and remove them and replace with the modern variety. The modern variety allows a couple lugs to be mounted as the stud is now on the "fused" side and the isolation bushing is in the terminal base.

Also note these terminal blocks will cost $35 or so from Bluesea but can be had from waytech for under $15
Thank you for this note. Does that mean in this picture the stud is not electrically connected to the base? So if the lugs that sit on top of the MRBF touch the stud, they would not bypass the fuse?

Thank you for the tip about WAYTEK. We also had noticed that BlueSea reselling other brand products.
 
You appear to be replicating approximately 1/2 of what I am installing. So quite glad to get the fuse and breaker information. I had planned to run 2/0 or 4/0 wire to my Victron Multiplus II 12 / 3000 unit. The documentation specifies using 2 1/0 leads for both the Positive and Negative Battery Connections. So I will install a 300 amp disconnect on the positive lead from each of my batteries and also configure a switched 100 watt 50 ohm resistor pre charge circuit across the battery disconnects to pre charge the capacitors of the Multiplus II. Will also configure the same switched 100 watt 50 ohm precharge circuit across the 50AMP breaker/disconnect attached to each of my Epever 40 Amp solar charge controllers (using the same one you are) only 2 as I will have 2 sets of 2 series connected 210 Amp solar panels and 2 of the 40 amp SCCs are much cheaper than 1 80 amp.
 
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