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HRTKD

Boondocker
With 2/0 cable, how short a distance with a curve is possible? This is welding wire and it's supposed to be very flexible. But I've never worked with it before and don't know what it's limits are.
 

HRTKD

Boondocker
I want to thank everyone that provided feedback in this thread. My system is mostly up and running. No smoke, sparks or fire. :)

The only part that isn't complete is the ground-based solar panels. I need to finish the wiring for that and build an adjustable angle frame.

I will be redoing some of the wiring in the picture below. I ran out of the right size and color of heat shrink tubing and that will be addressed soon. I have a few wires that need to be secured. The 2/0 cable on top of each battery is at the top of that list.

The battery on the left was my first. I am not happy with the BMS wires. I learned from it and the battery on the right came out better.

20200903_190817.jpg

I did end up splitting the electrical system into two distinct circuits. The existing 150 watt panel and PWM controller feeds into dual Trojan 6v batteries that will be powering only the generator starter, the tongue jack and the trailer breakaway brakes. The truck charges this circuit through the trailer 7 pin. The new system does not get any charge from the truck's alternator.

The new system is likely to solve some of the power quirks I've had. The bunk bed, located at the rear of the trailer, would sometimes not function. Given the size of the wire and the distance from the battery, I suspect there was a critical voltage drop. If I were to measure the wire from the battery to the bunk bed's motor, I suspect it would be a minimum of 30', maybe even 40'.
 

HRTKD

Boondocker
Is there a surge protector between the shore power and the converter?

There is. I have one that plugs into the pedestal. It rarely gets used as I'm hardly ever someplace that is a formal campground. There is a circuit breaker upstream of the converter also.
 

Hovanic

New Member
HRTKD

Nice Build! I am envious.
Your system is pretty much exactly what I want to do in my RV. (not sure I have enough room)
Have you updated your solar design pdf as built? Would love to see that.
Thanks
 

HRTKD

Boondocker
HRTKD

Nice Build! I am envious.
Your system is pretty much exactly what I want to do in my RV. (not sure I have enough room)
Have you updated your solar design pdf as built? Would love to see that.
Thanks

Thanks. I'll get around to it. I'm headed out of town for a week to put the system through its paces. The inverter, with no load on it, has already given a clue that it doesn't like 95° F days.
 

Hovanic

New Member
@HRTKD I have been studying your install while planning mine. It should be almost identical.

I have a couple hopefully simple questions.
1. Did you end up using DC Circuit Breakers for your solar panels? Are they mounted in the lower right of the picture you posted? Looks like it is mounted to DIN Rail?
2. What size system Buss Bars did you use? 250amp?
3. The Overkill Solar BMS did you upgrade to the 8ga wires or stick with the 10ga? 12" or 24"

Thanks for documenting so much of your system.
 

HRTKD

Boondocker
@HRTKD I have been studying your install while planning mine. It should be almost identical.

I have a couple hopefully simple questions.
1. Did you end up using DC Circuit Breakers for your solar panels? Are they mounted in the lower right of the picture you posted? Looks like it is mounted to DIN Rail?
2. What size system Buss Bars did you use? 250amp?
3. The Overkill Solar BMS did you upgrade to the 8ga wires or stick with the 10ga? 12" or 24"

Thanks for documenting so much of your system.

1. Yes, I used DC breakers, rated at 40 amps on a DIN rail: https://www.amazon.com/gp/product/B07YDZ4GFB. This product was a recommendation from another forum member. So far, they work good. But I haven't tested them out by shutting down the circuit at the peak of solar production.
2. The main bus bars are indeed rated at 250 amps. Fastronix 3/8" 4 Stud Power Distribution Block with Cover. I've found other bus bars that look exactly the same by other manufacturers. So I'm not sure who really makes this bus bar. I used these because I already had them from another project. In retrospect, a five or six stud bus bar would be easier to work with. But the extra space it takes up may not be worth it. The three small screw terminals on the bus bar will come in handy when I add smaller loads that originate in the same compartment. The battery heating pads will be the first item to make use of the screw terminals.
3. I upgraded the Overkill BMS order to have the 8 gauge wires, 12" long. I didn't get them with lugs/terminals. This was an issue that cost me time. As you can see in the picture posted above, the battery on the left (my first one) uses ring terminals on each of the three BMS wires. That was a lot of ring terminals to put on one battery terminal. It looked like crap and I ran out of 8 gauge ring terminals, so I switched to putting all three wires into one larger lug. That worked out a lot better. It's a cleaner install. One of these days, I'll redo the first battery. Don't ask me what size lug I used. It was either 2 or 4 gauge, I don't remember.
 

Hovanic

New Member
Hey thanks for the quick reply.

It does not appear you have a fuse on each battery pack. something like This. I read some another thread where it was advised to protect the individual battery pack. If one pack was off line (for some reason) and a 150amp load came in which would not trip your main fuse would the BMS protect against that or would one of the fuses linked above be a smart add?

I thought you had also mentioned somewhere that you were considering a Victron Multiplus 12/3000? The 2 overkill BMSs should handle the normal loads but not sure about the surge that the Multiplus is able to withstand. Have you given this any thought? Maybe this is a question for Overkill Solar?

Thanks again!
 

HRTKD

Boondocker
There isn't a load in my trailer that would exceed 90 amps. I tried to exceed that the other day with a 1500 watt space heater connected to my 1000 watt inverter. The inverter shutdown when it hit 90 amps, or something like that. I was watching the Victron BMV-712 to see what the amp draw was through the shunt.

I chose to go with a single fuse to cover both batteries. Those things are expensive!
 
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