Bypassing the avionics master??!

Here’s what I have 9679CDB3-5E1C-495F-9066-1279A55AC6D3.jpeg
 
Well, I should have said that I am flying an older C182 that has an upgraded panel with a garmin 430w and stratus 2s. what i'm looking for is a Cessna-approved wiring diagram that shows exactly what the alt avionics master actually does. thanks.
 
J_Pilot said:
Well, I should have said that I am flying an older C182 that has an upgraded panel with a garmin 430w and stratus 2s. what i'm looking for is a Cessna-approved wiring diagram that shows exactly what the alt avionics master actually does. thanks.
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Looks like a modification to me.

Checked the aircraft AFM yet? If that was added, there should be a section on what was done and what it’s for.

Secondarily it should also be in the aircraft maintenance records.
 
TangoWhiskey said:
I think the only way to "bypass" the avionics master switch (I presume he means so as to get power back to the avionics--what other reason would there be to bypass it?!) would be to use alligator clips behind the panel! Or, just continue VFR and land as soon as practicable.
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I have two avionics masters connected in parallel so that if one fails I can use the other. It's been that way since I bought the plane. They are functionally identical.
 
The avionics master allows you to conveniently shut all the avionics down so they're not on the bus when things are unstable (while cranking the engine or shutting down).
 
flyingron said:
The avionics master allows you to conveniently shut all the avionics down so they're not on the bus when things are unstable (while cranking the engine or shutting down).
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Also unless you installed separate power switches for them, many new radios, including the GTN series, have no power off function (soft or hard) at all.

Garmin really trusts their power protection circuits in them, I guess.

Installed hanging off the avionics master bus via a pullable breaker, for the hopefully rare case of one emitting magic smoke.
 
denverpilot said:
Also unless you installed separate power switches for them, many new radios, including the GTN series, have no power off function (soft or hard) at all.

Garmin really trusts their power protection circuits in them, I guess.

Installed hanging off the avionics master bus via a pullable breaker, for the hopefully rare case of one emitting magic smoke.
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I refuse to install any radio on the primary bus unless it says to do so in the STC. That being said I just had to add 4 breakers to primary bus to make that happen (G5s and all the associated equipment and the engine monitor must be on primary bus) in the process made a whole new breaker panel that fits an unused radio cutout on the copilot's side to hold the rest of them.

These old planes DONT have enough breakers as-is. It does now, and additional space to add more if needed. Since aircraft go through many small radio jobs over their lifetime few ever really get a good plan and the avionics bus fixed the way they should be.
 
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bnt83 said:
I refuse to install any radio on the primary bus unless it says to do so in the STC. That being said I just had to add 4 breakers to primary bus to make that happen (G5s and all the associated equipment and the engine monitor must be on primary bus) in the process made a whole new breaker panel that fits an unused radio cutout on the copilot's side to hold the rest of them.

These old planes DONT have enough breakers as-is. It does now, and additional space to add more if needed. Since aircraft go through many small radio jobs over their lifetime few ever really get a good plan and the avionics bus fixed the way they should be.
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Our installer was able to re-use unused breaker holes but change the breaker style to pullable. In hindsight because we didn’t realize he had to do that anyway, we probably should have just had them replace all of those breakers with pullable ones. Now we have three oddballs. And those old ones suck anyway.
 
There are many "single points of failure." The spam cans we fly are not designed with redundancy in mind.
 
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