InterAv Alt strange issue


Hi Guys,
I found a strange issue in my wiring. While troubleshooting this issue:
The Pos+ wire going to the OVR was connected to the output (bottom screw) of my Nav lights CB. (!?) Along with the navlights wire.

It has a piece of tape on the wire which reads "Connect to bottom screw, #9 Circuit Breaker". This is the Alternator CB, and the bottom is actually the alternator side of that CB.

Here's what I don't see. A 5A CB anywhere in sight. Ok, actually there is one that says "Fuel" and another that says "XPON", but the rest are not 5A.

This STC was installed in 1991 by an A&P in the pnw.

So maybe this thing is finally needing a replacement? Unfortunately I can't find a datasheet for the InterAV OVR (635-62448 ), so I don't know how much current that line draws. I also wonder if it could be the voltage regulator. Besides that weird issue (and the lack of a 5A CB available) the system seems to be installed correctly as the wiring diagram shown here.

So looks like my A&P and I have some work to do. Very frustrating. But maybe we're getting to the root of the issue.
Typically and alternator rotor coil draws a maximum of 3 amps with a full load on the alternator output. The current varies with the required alternator output so as to keep the output voltage constant.
The 5 amp circuit breaker protects the voltage regulator output and the rotor coil against shorts.

Attached is the Interav wiring diagram and the wiring diagram of my Clipper wiring with the InterAv alternator.
The Red Line alteration on the Clipper diagram is not there. I replaced the two 10 Amp landing and taxi light switch/circuit breakers with 2 amp switch/circuit breakers.


  • Interav Alt. Wiring.jpg
    Interav Alt. Wiring.jpg
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  • Clipper Wiring Diagram 4-16-2020  ED landing lights.png
    Clipper Wiring Diagram 4-16-2020 ED landing lights.png
    72.1 KB · Views: 32
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