Arcing battery bank.

[894tom]

Why would a battery bank start arcing? The inverter shut off with an error code saying low battery voltage error yet it read 52.8v. It would try to restart and every time it did a arc would jump from one of the terminal connections to the rounded portion of the battery terminal. Its hard to discribe on here. The battery post has the rounded flat portion coming out of the battery and then the 5/16 connector portion sticking out just to the side of it where you bolt your cable to it. Anyway the arch would jump from the connection to the flat round portion. I check the connection and it was tight as a drum. When I cleared the error code on the inverter the problem resolved itself. Things went back to normal status. Any advice.....other than stand outside about 50 feet away and hold out a marshmallow? Glad this did not happen when the banks where charging.

[Mike90250]

Crud inside the joint, even with the bolt tight ?? I'd power it down, pull the bolt off, and open the connection, and look carefully. clean and re-torque.

[894tom]

How about that....you are right. Couldnt see it without my glasses the first time. Just that little bit of buildup caused that arching. Goes to show just how dangerous wet cell batteries are. A wire brush solved the issue.

[Sunking]

It would try to restart and every time it did a arc would jump from one of the terminal connections to the rounded portion of the battery terminal.

I know exactly what it is:
Poorly terminated connectors...

You just escaped a major fire Tom

[894tom]

I had the connectors terminated professionally to the cable. I did not do this job as it requires special tools. I would certainly hope they did it correctly.

I did find a buildup of some sort on both the cable connetor and the battery terminal. It almost looked like a lime scale buildup. The part that was arching was chard between the battery terminal and the cable connector. I used a wire brush to clean it off the scale buildup and the charing. I disconnected the solar array and main power coming to the inverter then allowed the area to air out with a fan for about 10 minutes. I then commisioned the inverter again. The problem seems to be resolved. I am going to purchase some of that corrosion resistant gel to coat the terminals.

Do you still think its the cable terminations or do you think I found the problem. Sunking you know I have had this systme in place for over a year with no problems. Perhaps the terminal connection worked loose?

[Sunking]

Buy a can or tube of NO-OX-ID A Special grease and coat the terminals and connectors. The protection will outlive the batteries.

[894tom]

LOL....I have gloves on my hands getting ready to put it on as we speak. I already had bought a tube due to this issue.

[Sunking]

LOL....I have gloves on my hands getting ready to put it on as we speak. I already had bought a tube due to this issue.

Tom it works best if you melt the grease with a hot plate, then brush it on.

Is addition when cables are made, coat the wire skinner and the insider of the terminal compression connector before compressing.

[894tom]

Thanks for the hot plate tip.

The cable are already made up. There is no grease squeezing out or near the connector so my guess is they did not use that techinque.....but I will keep that in mind when/if I get them made up again.