On 12/7/2019 at 12:24 AM, GlennWest said:

My positive cables are 18" from batteries to bussbar. Negatives are 24". Negatives at bottom so they had to be longer.

George, that may well qualify for having "Overcurrent Protection" "At or Near" the energy source. Its been too long and I would have to look up the specs concerning amperage and wire size and voltage etc.  Again, the Magnum likely has its own built in limiting and overcurrent protection ON ITS OUTPUT and if so you're good FROM it TO the AC Distribution Panel

John T

Based on above suggestions I believe I'll go with fuse directly leaving bussbar. They will be virtually no way for my cables to short out. Short runs and plywood, not steel around it. I will also enclose this area so nothing going in there.

  On 12/7/2019 at 7:05 PM, GlennWest said:

Based on above suggestions I believe I'll go with fuse directly leaving bussbar.

Good plan Glenn, works for me and likely ???? complies with any applicable codes.

John T

Good plan. I only know the marine rule,  no more than 7 inches from battery positive. But with no metal, where could it short?

I like marine breakers they make a handy disconnect when the fire starts because those DC batteries are bizzy trying to discharge themselves to earth. 

If those lithium batteries goes up in flames, you won't get to the disconnect. But the BMS suppose to control this.

  On 12/6/2019 at 10:35 PM, Sehc said:

I do not trust breakers on high ampere dc circuits. I do use Blue Sea battery disconnect switches. I also use these MRBF on the bus bar.    https://shop.marinehowto.com/products/blue-sea-marine-rated-battery-fuse   They save a couple of connections each. A catastrophic fuse could be required at the battery before the bus bar if the cable length is too long.

I do believe I will get those MRBF fuses. Like less cables and space savings. also any reason why not on battery post? These little fuses would fit well there.The 3/8" ring would be a little large. Battery is just under 1/4" but metric, M6. Surface area is good though. Washer on top should cause good contact. Would need 3 instead of 2 but all my cables will be protection.

Edited December 8 by GlennWest

I used these on my battery terminals. I have had no problem after 3 years. I use a voltmeter to check for voltage drop when servicing my battery. The main problem is clearance above. These are higher than the posts.  The ring fits a  5/16 stud.

Edited December 8 by Sehc

add correct size number

I have feet above for clearance. Just what I wanted to hear. I could put a stud in my battery. 

Glenn, wow talk about any code requirements (NEC or Marine or RV)  to provide Overcurrent Protection for the feeders  "AT OR NEAR THE SOURCE" I think that pretty well has you covered...…...Id use those in a heartbeat provided they are the sufficiently rated for your current requirements ???? Also anytime you can reduce the number of cables and extra connections that's good.

Now that you have "Overcurrent Protection" well covered for the feeders FROM the battery TO Load Inputs, you can install a Disconnect at loads such as Inverters or others for safety and convenience and/or as required (Unit may already have that covered??) If you want a pure disconnect only or say a breaker suitable for switching that's between you and what the manufacturers suggest (don't want to void any warranty) and if its needed ???  but I prefer and have at least a disconnect method especially for loads far removed from my batteries. As you already know having the Inverter close to the battery saves on line voltage drop and wasted heat energy concerns...….

Although Marine Grade is great and typically high quality and corrosion resistant and has excellent vibration resistance, using it in strictly RV applications may or may not be absolutely required BUT ITS SO GOOD AND SUCH HIGH QUALITY I've used it and prefer it. I often (right now as a matter of fact) am dry camped right on a beach so Marine grade is a good thing required or not.   

I still want to camp right next to you and plug into your energy source as you have enough to power an entire zip code lol

John T