Questions on circuit breakers

Questions on circuit breakers

Postby Trevor Laundy » Mon Jun 07, 2010 9:07 am

I try to fly my my 1969 PA30 C D-GPEZ regularly, but occasionally the day job forces me to leave it hangared for up to a month, 2 or 3 times a year. I can usually anticipate and am in the habit of pulling all the circuit breakers when this situation arises.

My rationale for this is to prevent current 'leakage' over the longer times and there are also advantages in allowing me to select services progressively on start up ( I don't have a ground services switch, just radio master, so it is normally all or nothing. I also get to know which circuit breaker is which.

Questions:

1. Is my rationale correct, or even sensible?
2. While I can be sure all my circuit breakers are not jammed, am I weakening the trip mechanism or exposing the circuit breakers to unnecessary wear of some sort?
3. Does anyone else do this? I haven't noticed any disadvantages, yet.

I have a science education but not very electrical.

Thanks,

Trevor
Trevor Laundy
PA30 C Turbo non de=iced
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Postby Zach Grant L1011jock » Mon Jun 07, 2010 11:53 am

Trevor,
Pulling breakers with the master switch off does nothing. The power stops at the battery relay so no benefit one way or the other on pulling breakers for storage. As for start up, about the only thing I can think of that is not switched that might be of any significant draw is the Turn Coordinator...everything else is switchable elsewhere (one you don't want to pull is the tip tank solenoid, otherwise you will not be able to check for tip operation on preflight). Now, as to your question in the light of doing a ground clearance etc, yes, you can pull all the breakers on the avionics except for the one radio you will be using...that is fine, just don't forget to push them back in. As long as you have good breakers, then this should not cause anything bad to happen. It may shorten the life somewhat (measured over many years though), but it certainly is common practice on many of the older transport types.
-Zach
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Postby Trevor Laundy » Wed Jun 09, 2010 9:09 am

Trevor Laundy
PA30 C Turbo non de=iced
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Postby Zach Grant L1011jock » Wed Jun 09, 2010 3:30 pm

Last edited by Zach Grant L1011jock on Wed Jun 09, 2010 6:24 pm, edited 1 time in total.
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Postby Jay » Wed Jun 09, 2010 4:46 pm

Jay
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