Mystery Electrical Component

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elliotblock
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Mystery Electrical Component

Post by elliotblock »

Greetings,

Can anyone identify the black electrical component under the throttle cable in this photo?

Thank you!
Elliot
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6643
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Re: Mystery Electrical Component

Post by 6643 »

At this point I would be making a wild guess (and if I'm right, it's not approved.) Where do the three wires on the right side in the photo go? Two appear to go to switches; what do they control? Where does the green wire go?
4390
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Re: Mystery Electrical Component

Post by 4390 »

Looks like it might be a thermal breaker. Opens when overheated and closes when it cools off.
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Re: Mystery Electrical Component

Post by 8187 »

Wave modifier for the radio?
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Re: Mystery Electrical Component

Post by 2356 »

Circuit breaker. Check the parts manual pertaining to optional equipment.
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6643
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Re: Mystery Electrical Component

Post by 6643 »

4390 wrote: Thu Feb 27, 2020 8:39 am Looks like it might be a thermal breaker. Opens when overheated and closes when it cools off.
That was my guess, too. Auto-reset circuit breakers are prohibited. Also, breakers must be "trip free", which means you cannot hold the button in to keep it from tripping.

I overstated my point. The FAA wording is "not recommended" as opposed to "prohibited".
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Re: Mystery Electrical Component

Post by 6298 »

I know I have seen one and probably have it in my not well organized stash. The switch panel for the 47&48 140 has a cutout for the part in the picture, buy I don't see that part in the diagram. In optional equipment, it shows it as a disconnect Switch for the stall warning indicator.
Randy Thompson A&P IA Pilot
Hold STC SA547EA for installation of O-200 engine in Cessna 120/140 and 140A"s
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6643
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Re: Mystery Electrical Component

Post by 6643 »

I'm thinking it must be some sort of circuity protection device. One side is connected directly to the unfused buss and the other side to two switches. (The green wire is also unfused...)
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Rob Swanland
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Re: Mystery Electrical Component

Post by Rob Swanland »

Elliot, I think the mystery part is something the little leprechauns installed while your nice little 140A was hibernating. I think you should post a few pictures so everybody will know what I am referring to...
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Re: Mystery Electrical Component

Post by 6863 »

Elliot, that is the old emergency auto land system from 1946.
John Kliewer

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