Question:

Connecting this inverter to my RV. Using 2/0 wire from battery to inverter. What size breaker/fuse would you use?


thanks
George

 

How much is your realistic max AC power load? I run 4/0 wires from the battery bank and manual switch to a 2000w prowatt inverter with a 200A fuse from a 450Ah total 12v solar power bank for house backup power. I use 2/0 from the charge controller to the batteries to reduce voltage drops when charging.

 

Nice setup! from the panels I expect between 20-30a, so I am curious as to why you have such fat wires from the controller to the batteries. Are you sending a large load over? I was happy with 10awg!

As for the expected AC load, I would never really expect more than 2000w... But I want to compensate higher to give some leeway.

thanks!
George

How much is your realistic max AC power load? I run 4/0 wires from the battery bank and manual switch to a 2000w prowatt inverter with a 200A fuse from a 450Ah total 12v solar power bank for house backup power. I use 2/0 from the charge controller to the batteries to reduce voltage drops when charging.

 

3000 watts from a 12 volt supply is 3000/12 = 250 amps. This would be the current if the inverter was 100% efficient. The inverter will probably be about 80 % efficient so the current will be about 250/0.8 = 312.5 amps.

Les.

 

Nice setup! from the panels I expect between 20-30a, so I am curious as to why you have such fat wires from the controller to the batteries. Are you sending a large load over? I was happy with 10awg!

As for the expected AC load, I would never really expect more than 2000w... But I want to compensate higher to give some leeway.

thanks!
George

Two reasons.
1. I built a custom solar data/control system that monitors the voltage at the battery terminal, at the charge controller and just about any other useful voltage data-point. So I collect and view tons of operational data on my system.

https://forum.allaboutcircuits.com/...rolled-battery-array.32879/page-3#post-857361

At 40A of charging current there was a very noticeable voltage drop due the the size of the original charge wires. While in the BULK charge stage (max current) this is mainly just a resistive loss in the system but when the charger switched to steady voltage controlled ABSORPTION mode this voltage drop reduced the recommended voltage actually at the battery terminal to a value below the battery type setpoint of the charge controller because it didn't have remote voltage sense to make the correction. (its an old PWM C40) Precise float and charging voltages (with proper energy cycling) are critical to top performance longevity The easy solution was to increase the size of the interconnect to eliminate the voltage drop and keep the voltage steady across the usually charging current range.
http://www.ecmweb.com/content/why-batteries-fail-prematurely

2. I'm a Pack-Rat dumpster diver with sheds full of large copper wiring from work.