What can happen with a bad crimp
31 August 2011 | Annapolis, MD
Benno
Once upon a time you smell smoke. We don't smoke, it wasn't a barbecue and it wasn't our neighbor grilling brats. "It must be coming from the outside, someone burning trash," I said. But no, "There is smoke coming out of the batteries," Marlene declared. "Oooh yeah" Missis bad news. Close enough, the smoke walled out of the lid underneath our 120V AC wall with the generator control panel, the two 120VAC distributor panels and the inverter control panel.
Hastily I switched everything off and started to nose around.
First, the top panel of the generator control came off. It was fine. Then I moved on to the larger panel in the middle. It was NOT fine. Actually, it looked bad, really bad. Cooked wires, cooked 30 Amp main breaker. What had caused this mess? It didn't take me long to find a bad crimp on a ring terminal, the one on the a black 10 AWG wire, which runs from the main breaker through a pickup coil to the main bus. Originally the panel came prewired and the bad crimp took 6 years to almost start a fire. Was it a Monday morning crimp?
Funny, Marlene is thinking this happend now with the new generator installed. She has a good point there.
The old 1 cyl. diesel gen set labored heavily and slowed down when we were using more than 18 Amp. The panel harbored already the bad crimp, but the bad crimp still managed to provide 18 Amp. Now, with the new 3 cyl. Northern Light diesel generator installed, which easily manages 30 Amp, we used sometimes the electric on demand water heater. This one drew 18 Amp when going and on top of this the watermaker was running, which drew another 12 Amp. Do your math, this is equals 30 Amp. So this bad crimp got overloaded and heated up to the point where it started to smolder.
Naturally I replaced everything new, the ring terminals, the double 30 Amp breaker and the wires. For crimping I used an onboard professional crimping tool.