[C320-list] Battery Charger Sanity Check

[Jeff Smith]

Hey Everyone,

I need a second opinion. My 30Amp Newmar charger stopped charging the batteries after a static discharge, although the AC side of the charger continues to work. Inside the charger there is a high output, 100Amp Bussman fuse. I checked resistance on this fuse and it read open, which I interpreted as a blown fuse. I ordered a new fuse, reinstalled the battery charger, and there is no change. The AC side continues to operate. Obviously I now suspect the charger, but I do not want to put a new charger in and have there be a short somewhere else. The reason I am at least a little worried is because I had some pretty severe arcing as I tried to reconnect the battery leads to the charger. In fact, I ultimately took the leads off the battery, connected them at the charger, and then re-connected them at the battery.

Here are my thoughts. If I test the two positive leads for both of my battery “banks” using the common ground wire (I am testing them at the point where they connect to the battery charger), they read 12.8 – 12.9V. This suggests to me that there is no short in the wires. I am getting 110 into the charger, and there is also 12.8 or 12.9 on the wires connected to the batteries, then the only bad part of the circuit must be the DC output from the battery charger. The DC Amperes gauge on the front is also reading 0 Amps when energized.

I am probably being overly cautious, and I have ordered the suggested 40 Amp charger, I just don’t want to zap it if there is some other issue. CINC-House (my wife) will not be happy if this happens due to technician error.

Thanks in advance for any thoughts.

Jeff Smith
Sailmates, 1994, #121