lifepro upgrade need help mainly with wire sizing

[dan0rl59]

I am upgrading my current system which is 30a pull behind camper with 2 lead acid batt. I have a basic pwm charge controller hooked up to the batteries and a plug that I hook up a 200 watt suitcase to when boondocking. I will put in 200ah lifepro4 and would like to add in a cutoff switch on positive side then run into fuse then a bus bar. on neg side want to run into smart shunt and into bus bar then into a renogy 20a mppt charge controller I will run the plug into charge controler so i can continue to hook up my panels that way. what I am having a hard time figuring out what gauge to run from batt into the shut off/ fuse shunt and bus bars. my panels currently run 10awg which I believe is more that enough and I think is the largest size that will work with the controller all the runs should be pretty short as I am doing this all in a small area i want plenty of wire but not so large that it becomes difficult to use I've watched you tube and read stuff I seem to just be making myself more confused

 

[Dave in AZ]

Wire sizing and fuse and cutoff switch FROM the battery all depend on what LOAD you pull from the battery. Has zero to do with your panels or mppt controller that inputs TO the battery.

What voltage, you didnt say, with 2 batteries it could be 12 or 24?
What loads do you have? Is there an inverter, if so how big?
Most 12v 200ah LiFePO4 batteries have BMS that can punch out 100 amps, how much are you using?

Rewatch Will's video on sizing conductors. If you haven't already, watch every video in that playlist, "Beginners start Here, basics of electicity".

 

[dan0rl59]

its a 12 volt system no inverter mostly would just be running standard 12 volt stuff biggest draw might be heater fan during cooler months fridge is propane so just lights maybe a fan and maybe some radio Im looking at two batteries onw has a 100 amp bms another has the 200 its a basic system we just use the solar to lessen the gen time we just need new bats so i think its time to upgrade and I understand I will need to change out converter too I think the currant cables running to the camper are 6 awg

 

[Reed Cole]

Your existing converter may be fine for lithium, especially if you don't leave it plugged in for extended periods of time.

I would recommend making a diagram with make and model of components and approximate lengths of wire runs. It's a lot of work to decipher what's going on from a block of text.