rdockery_3
Active Member
I made a post on here earlier this week about my Silent Hektik regulator possibly going bad. We were about 30 minutes into a flight when I got the low voltage alert and constant negative draw on the amp meter. I ordered a John Deere regulator and went to the hangar today to intended on replacing it. While I had the cowling off I just decided I'd put a multimeter on my battery to see what it said. Since we ran solely on battery power for over 20 minutes the other day after the low voltage alert I was curious how low it was, but to my surprise it was 12.7 volts. So, I thought I would have my son fire up the plane and I would the multimeter on the battery with the engine running and the Silent Hektik regulator still hooked up. He fires it up and the D180 shows that the battery is charging just fine. After this, we shut the engine off and put the cowling back on. I figured I'd do a run up and possibly a short test flight to see what happened. Run up showed normal charging, so I flew for about 30 minutes and everything was fine. While I was flying I got to thinking that maybe the main bus fuse backed out or something, which is what caused the low voltage problem the other day, because I had checked the fuse the other day to see if it was blown. It wasn't blown so I just pushed it back in and in my mind I'm thinking maybe it had just backed out. Ok, so here is the really interesting part that maybe some of you guys can help me understand: I decided to pull that fuse after I landed just to see what would happen. I pulled it and as expected I get low voltage again and no charging (no surprise there), but when I put it back in I could not get a charge either. I brought the RPMs up and still constant negative amps and low voltage. I shut the engine down and immediately fired it back up and lo and behold the charging system is working fine again. Was it the master being turned off and back on that caused it to start charging again? Once that main bus fuse is pulled out does the voltage regulator have to sense the master being cycled off and on again to allow charging? If so, the 30 amp main bus fuse may have worked its way out the other day and that would explain why I got no charging even after pushing it back in.
