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By NDB_hold
#1611350
On typical Piper (and many other) aircraft there are basically two types of circuit breaker: one type is flush when pushed in, and the other has a mushroom shaped head. The latter of course can easily be pulled or reset if required (or zip tied off), but is there a way to manually pull or reset the former?
User avatar
By Trent772
#1611447
You can't pull them, but you can reset them.

Big question is..... why would you :wink:

If it popped, usually it was for a good reason and you should look at it when on the ground.
Bobcro liked this
User avatar
By NDB_hold
#1611471
Because we had smoke from the wiring to the ventilation fan, and rather fancied isolating it rather than having to turn off the master. Luckily this was during taxy to parking after landing, although it did give us an exciting few minutes. Being able to pull a CB could have been vital in flight, though.

Not using the fan turned out to be a good solution...
User avatar
By PaulSS
#1611482
That, to me, sounds suspiciously like the current value is too high on that CB. Seeing as they are there to protect the wiring, I would have expected the CB to have tripped some time before the wire started smoking.

I thought about buying those flush CBs because of their price but decided that I would want to be able to trip a CB manually. Sounds like a good decision for once :)
User avatar
By Trent772
#1611489
NDB_hold wrote:Because we had smoke from the wiring to the ventilation fan



Sorry, I meant why would you want to reset, not pull :oops:
User avatar
By NDB_hold
#1611516
PaulSS wrote:That, to me, sounds suspiciously like the current value is too high on that CB. Seeing as they are there to protect the wiring, I would have expected the CB to have tripped some time before the wire started smoking.

I thought about buying those flush CBs because of their price but decided that I would want to be able to trip a CB manually. Sounds like a good decision for once :)


I think you are right - checking it we could see a much larger movement on the ammeter than was reasonable for turning on a ventilation fan yet the CB didn’t trip.