HI all! 2023 31T13 with single solar panel. 30 Amp shore power. Upgrading from 2 deep cell Interstate batteries to 2 100 Ah lithium. The current battery cables used to put the two batteries in parallel are 2 GA. Are those big enough to reuse or do I need bigger cables? Any other cables I need to upgrade? Also, since I don't have a disconnect for the solar panel, I assume I just disconnect the orange and black wires from the solar charge controller and cap them until everything is swapped out? Thanks for any input. Much appreciated!
Upgrading to Lithium...questions
- Thread starter renobruce
- Start date
BryanValRox
Elite Member
Evening, your question regarding cable size really depends on the amount of load you will be placing on it.
Generally speaking, it depends on the voltage, conductor type, length and load on the circuit , insulation rating, bundle size and the duration of the load. I have seen ratings of 90 to 130 amps on 2 ga.
2 Allies
Prominent Member
renobruce,
As Darrell and Bryan said you will be fine. We switched out our LA battery for a 400AH Lithium and it has been great. Just remember to change the switch on the converter from LA to Li if you have the same setup. We have the one 320 watt solar panel that does a great job keeping it topped off.
Good Luck,
Bruce
As Darrell and Bryan said you will be fine. We switched out our LA battery for a 400AH Lithium and it has been great. Just remember to change the switch on the converter from LA to Li if you have the same setup. We have the one 320 watt solar panel that does a great job keeping it topped off.
Good Luck,
Bruce
BryanValRox
Elite Member
In addition to what Bruce said about the converter switch being changed over to LI, you will also need to change the setting on the solar controller to LI as well.
Average Man
Member
After having been in the Utility for over 35 years it worries me when someone says "Should be fine to just swap the batteries and not worry about cables honestly". As a subject matter expert on Lithium batteries, your LiIon batteries are going to put out much more instantaneous energy than the lead acid batteries. Your cable sizing should be based on your loading as was mentioned previously. For instance, my 2000W inverter can draw up to 250 AMPS. To safely handle this load I checked the National Electric Code and determined for my load, I needed 2/0 cables. Since I use a bus bar to make my connections I have a 250 Amp rated busbar with 2/0 cables from the batteries to the bus bar and then to the Inverter. I have smaller gage (6 Awg) for my 60 Amp solar charger. If you are not a math whiz, have someone sit down with you to work out the loads, check that against the National Electric Code, and prevent your trailer from going up in smoke. Not trying to disrespect anyone, but prevent problems down the road by doing it right the first time.
While your information is correct, if your read the original post, there is no mention of an inverter. The 2 gauge will be fine for their 12v requirements.
Average Man
Member
Jim, point taken, you are correct. I guess I just wanted to point out that as people make upgrades to their trailer, they need to consider cable size that take into account their loads. Since he is now putting in Li Ion batteries a 100 Ah battery can provide 1280 watts depending on battery. At 200 Ah 2560 watts. On a 12 volt system that is 213 Amps. At a minimum that is a 1 awg wire if he hooks up loads in the future (like Inverters). Just want to make sure people consider that when making upgrades to their trailer.
Do you feel like you have enough information to back your opinions here? Do you know how much inverter they have? If they were working fine with 2 batteries before, they will be working fine with 2 batteries now using the same cabling. How much batteries can put out is not important. It is what will be drawing current. That draw is what would dictate the power cable size, not the maximum the batteries can put out. Then protect the cables with appropriate type/size fuses. If they upgrade equipment, sure, start looking at the increased load. Until that happens, the current of the load has not changed just because the batteries did. Same cables will be fine. Yeah, I work in utilities, too.