TVATIVAK71
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Just replaced a B&C 201-1 with another of the same. The original issue was it seemed to be normal and the tolerances checked out fine with multimeter on the trouble shooting sheet. but at times (once every 6-7flights) while revving engine to turn around volts would spike over 15 and alt field cb/switch would trip. Figured I’d just try a new regulator.
Anyway I assumed changing it would be a plug and play. That’s how I’ve always treated them when changing out. Started it with only master on, then while running turned on alt field and avionics master. Immediately voltage indicator (CGR-30P) goes from 13.3 to 9.9 then super thick noxious smoke comes rolling from under panel. Shut it all down blew an extinguisher........yada yada yada.
When the smoke cleared the Alpha Systems AOA indicator (was in plane when acquired, ironically planned on removing it soon) CB was popped. The AOA indicator on dash has a coax cable to the magic brain box. This cable was very long and coiled up with two other AOA system cables. From the dash indicator coax connection to the brain box was completely torched and cable coverings were burnt and melted together.
After inspecting all the wires around the burnt stuff. Left AOA breaker out, started engine all indications good except voltage cycled from 9.3 to 13.8 several times then up to 14.2 at 1200rpm. Shutdown, started again this time no cycling volts just 13.9 at idle and 14.2 at fast idle. Did mess with pushing breaker in to see results (I know I know.....) no smoke, no heat. AOA indicator cycles though read outs then totally extinguishes. Forgot to check amps.
This just happened a few hours ago and now I’m starting the voyage of discovery and research on why this happened so I haven’t covered very many bases yet. Maybe that AOA system realized it wasn’t doing much good and decided to self destruct on the annual. It’s coming out now along with a thorough under panel inspection for any other damaged items.
So my question is after reading support literature for the regulator installation. Is it really just plug and play or did I omit some procedure to properly install?
Just gathering thoughts for now, I have to look forward to some under panel playtime. Cockpit fires scare me, had one once in a C-207........not fun. Today was a good lesson for a newly minted private pilot who was watching how quick, thick and toxic a cockpit can smoke up.
a crude pic of some burnt wires and pic of those coiled wires from AOA manual.
Anyway I assumed changing it would be a plug and play. That’s how I’ve always treated them when changing out. Started it with only master on, then while running turned on alt field and avionics master. Immediately voltage indicator (CGR-30P) goes from 13.3 to 9.9 then super thick noxious smoke comes rolling from under panel. Shut it all down blew an extinguisher........yada yada yada.
When the smoke cleared the Alpha Systems AOA indicator (was in plane when acquired, ironically planned on removing it soon) CB was popped. The AOA indicator on dash has a coax cable to the magic brain box. This cable was very long and coiled up with two other AOA system cables. From the dash indicator coax connection to the brain box was completely torched and cable coverings were burnt and melted together.
After inspecting all the wires around the burnt stuff. Left AOA breaker out, started engine all indications good except voltage cycled from 9.3 to 13.8 several times then up to 14.2 at 1200rpm. Shutdown, started again this time no cycling volts just 13.9 at idle and 14.2 at fast idle. Did mess with pushing breaker in to see results (I know I know.....) no smoke, no heat. AOA indicator cycles though read outs then totally extinguishes. Forgot to check amps.
This just happened a few hours ago and now I’m starting the voyage of discovery and research on why this happened so I haven’t covered very many bases yet. Maybe that AOA system realized it wasn’t doing much good and decided to self destruct on the annual. It’s coming out now along with a thorough under panel inspection for any other damaged items.
So my question is after reading support literature for the regulator installation. Is it really just plug and play or did I omit some procedure to properly install?
Just gathering thoughts for now, I have to look forward to some under panel playtime. Cockpit fires scare me, had one once in a C-207........not fun. Today was a good lesson for a newly minted private pilot who was watching how quick, thick and toxic a cockpit can smoke up.
a crude pic of some burnt wires and pic of those coiled wires from AOA manual.