12v electrical draw question

[1361]

I'm in the final stages of acquiring the parts for my inverter install. I'm gonna run the main line going from the original batts to a 400 amp buss bar. I want to put a circuit breaker just off the buss bar. It's only a small difference in price between the 50 and 100. I figure it's for a dead short protection. So the 100 would be OK. Is there any reason I shouldn't go with the 100 and use the 50? Perhaps use fuses instead?

What is the total max draw rating on something like this? I'm not sure about the wire size, but I think it might be either 6 or 8 gauge.

2020 Timber Ridge 25RDS mountain is if matters.

[twinboat]

What size inverter are you installing ?

The breaker/fuse and cables need to be large enough to handle that, plus 10%.

2 gauge is the minimum for a 1000 watt inverter. And that with a short run.

[1361]

I'm installing a Magnum MS2812 inverter. I have 3 SOK LiFePO4 batteries, but I managed to make room for a fourth. When it arrives in Sept., I'll add it in. I'm going to run 4/0 cables to everything.

My question is in regards to hooking up the existing trailer's 12v wiring onto the buss bar/distribution block. I'm just planning on using the existing cable that goes to the existing batteries up front. I'm not sure of the gauge of that wire. I believe it's 6 or 8 gauge. I want to run an additional circuit breaker just off the the buss bar. The small circuit breakers under the trailer do not make much since. The main wire coming in has a 30 amp breaker. Then it spits off into different circuits. One of these circuits has a 40 amp breaker. So, something isn't quite right down there. That's not unusual from what I've read here. I plan on checking everything out while cleaning everything up down there. But I still want to protect it just off the buss bar. A 50 amp CB would probably do the trick. A 100 amp is just a few dollars more and would allow room to add things latter without taxing the original wiring and loads.
Perhaps I'm overthinking this. I can get 3 x 70 amp anl fuses with a fuse block for 10 bucks at the big river. This might be an option as well.
Is there a way to tell what the total 12v max draw is on the original trailer wiring? Just adding up the fuse rating in the fuse panel inside puts the amp draw above what the original battery cable could adequately provide.

[LearningMore]

Originally Posted by 1361

...
Is there a way to tell what the total 12v max draw is on the original trailer wiring? Just adding up the fuse rating in the fuse panel inside puts the amp draw above what the original battery cable could adequately provide.

The DC side of my converter says "75 amp max panel current", so it seems to not want more than 75 amps.

I measured all the DC amps for each DC load on my trailer using a Fluke clamp meter. The largest draw was the slide motor at 12 amps. Some of what I have on my 22FQS overlaps what you have on your trailer. Here is a link to the spreadsheet showing all the loads:

https://docs.google.com/spreadsheets...it?usp=sharing

Hope that helps....

[wolfe10]

Originally Posted by LearningMore

The DC side of my converter says "75 amp max panel current", so it seems to not want more than 75 amps.

I measured all the DC amps for each DC load on my trailer using a Fluke clamp meter. The largest draw was the slide motor at 12 amps. Some of what I have on my 22FQS overlaps what you have on your trailer. Here is a link to the spreadsheet showing all the loads:

https://docs.google.com/spreadsheets...it?usp=sharing

Hope that helps....

NO. 75 amps is the maximum CHARGE RATE. Nothing to do with draw. Your batteries provide the "stored amps" to run your stuff.


Yes, if your draw is less than 75 amps, the draw on the batteries can be minimal.

[LearningMore]

Attachment 340169

Originally Posted by wolfe10

NO. 75 amps is the maximum CHARGE RATE. Nothing to do with draw. Your batteries provide the "stored amps" to run your stuff.

Yes, if your draw is less than 75 amps, the draw on the batteries can be minimal.

Thanks. I was looking at this picture and the fuses are for the 12v circuits and the 75 amp statement was next to them so in my mind they go together. This is a Progressive Dynamics PD4060K which is called a 60amp converter/charger.