Steps to reinstall batteries and replace inverter

[Treblemaker]

Several of you gave me great tips when our inverter started smoking when we hooked the battery cables, and now we are ready to tackle the replacement. The dual 6v lead acid batteries have been out of the camper for 3 months, as we have no electricity or light in the storage shed. They are charged and ready to go. Our camper is a 2015 model 21.

We need to make sure our steps are correct before putting the batteries back and purchasing/installing a new inverter. We have pulled the camper home to do the work, so it is outdoors. Here is where we need clarification from experienced users to avoid damage, reverse polarity, etc.

Battery connection to protect charge controller and avoid arcing:
1. We have 1 MC4 connection from the solar panel disconnected, and also covered the solar panel as a precaution. Is there anything else we should do before proceeding?
2. We would like to remove the dead inverter before putting the batteries back in. If we do so, can we just isolate the cables running from the battery to the inverter until the new one arrives?
3. Also we want to make sure we put the battery cables on in the correct order. We plan to put the small cable that connects Battery 2+ to Battery 1 -, then all the Battery 1 + cables, then Battery 2- cables. Last, the wires that go to our suitcase solar panel port. If this is correct, should we also use a resistor between the battery 1+ Cable and battery terminal to pre charge and protect the controller?
4. After the batteries are hooked up securely, are we ok to just hook the MC4 cable together and remove the cover from the solar panel?
5. does the battery 2 - cable go to a ground on the trailer frame?

Inverter install
6. For the inverter install (we have a Samlex set up so will stick with the same brand inverter), is it best to cover our solar panel for that also? Then use the resistor between the + wire of the inverter and touch it to the battery 1+ ( with the fuse) for 5 seconds, then hook it to the battery terminal? Lastly, after testing under load with the outlets on the inverter, we will plug it into our system (transfer switch and all outlets.)

Many thanks for your patience. We have done wiring in our home and a simple solar setup in our previous Casita, but the Escape set up is something we always worry about getting right. I trust the Escape hive mind to let us know what we are missing/incorrect about. Thanks again!

[John in Santa Cruz]

generally, the negative terminal of the power center goes to chassis ground.

re: order, yeah, sounds good to me. I wouldn't bother with any resistor like that.

re; wiring the inverter, I would hook both wires up at the inverter DC input side first, 200A or whatever fuse holder in series with the + wire, then connect - to battery -, and + to battery +, then install the fuse in the holder. 200A DC fuse would be appropriate for a 2000W inverter. Note you need some serious gauge copper wire for a 2000W inverter, like AWG 1/0, or dual AWG 4 in parallel for each leg.

[Treblemaker]

Thank you! Looks like we will need to add a fuse-the only one I can find is the blade fuse on the battery 1+! But we can and will do so as well as making sure wiring is sized appropriately. I appreciate your help and expertise!

[John in Santa Cruz]

Originally Posted by Treblemaker

Thank you! Looks like we will need to add a fuse-the only one I can find is the blade fuse on the battery 1+! But we can and will do so as well as making sure wiring is sized appropriately. I appreciate your help and expertise!

200A+ DC fuses need to be considerably beefier than a blade fuse.

this is a class T fuse, which is designed to blow extremely quickly, I think this one is 225A to 400A... its also quite large, and designed for like 1/0 and larger wiring lugs, with 3/8-16 terminals.

[Treblemaker]

That is what we will get! Looks like an easy install and good insurance, I wonder why we don’t have one (or similar) in our current set up? The whole inverter setup was installed by Escape! No wonder our inverter blew… But we do have some other strange things, such as the inverter wiring runs under the battery box, and the inverter was installed so close to the battery box that nothing could plug into the inverter…taking care of all that now as well.

[John in Santa Cruz]

oh, and if you have a 200A or whatever inverter off your two paralleled batteries, the wires connecting the two batteries in parallel should also be 1/0 gauge.

[Treblemaker]

I would not have thought about the connecting cable between the batteries! But it makes sense! Thank you!!

[Treblemaker]

I just wanted to thank you again for all your advice and help! Our inverter came in yesterday and we installed it today. Everything is working great, 220 amp fuse installed, etc. Hubby and I were pretty nervous about this and your instructions were gold! I am now happily playing with my small appliances and prepping for our NM trip!