Art,

I had a similar problem with my 320 one year ago. Actions done: Alternator checked and all the connections were OK.
Got very helpful advices from B&C.
In the end I changed the B&C Voltage (14V) regulator to the latest Revision (guess it was at this time Rev C).

[BTW, I placed the new regulator Into the cockpit area. The defective one (Rev A, 1995) was located firewall forward side (bad location for electronics...). The problem was solved and it works – since this improvement - very stable.

Good luck!

Patrick


Am 21.07.10 22:00 schrieb "Art Jensen" unter <flycassutts@yahoo.com>:

My volt 1 circuit breaker off the field of the altenator keeps tripping when I cycle the gear.  This happens 100% of the time when going up and 20% going down.
 
What I have done:
 
The altenator was sent to Quality Aircraft in Tulsa and bench checked putting out 75 amps under load.  The tech. stated that the altenator is as good as you could hope for one to be.
 
51/2 amps was run through the circuit breaker and it did not trip.
 
Replaced the battery
 
checked for loose connections and worn wires.
 
This is in a io-550 Legacy with a 14 Volt system.  It has been runing trouble free since March 2004 until one month ago.  Has anyone experienced this problem or have any ideas on what else I should check.  My A & P is out of ideas as am I.
 
The plane has a B & C voltage regulator which is said to be very dependable and in most Lancairs.  At this time it is not suspected to be the problem.
 
Thanks in advance for any input.
 
Art