Craig,
As a first start, check your ground wires…all of them, and especially the grounds to the B&C regulator and the regulator case. These regulators have an overvoltage protection circuit that works by tripping the field breaker. This circuit is easily triggered by spurious noise in the electrical system caused by bad grounds. Loose primary wiring will also cause this, but not as easily. Don’t be tempted to just install a larger breaker as one Lancair owner did!

 

I have the same setup you do, and have had no problems at 450 flight hours to date. If I can help you troubleshoot, contact me off-line.

Bob

757-286-4802 cell

 

Craig Berland wrote:

My IV-P has a charging problem.  The alternator 5 amp field circuit breaker pops.  It seems to take longer to pop when there is a higher electrical load.  For example when the air conditioner is running.  I have a 24v system, 100 amp alternator, B&C voltage regulator and  two 12 v gel cell batteries in series.  Any thoughts as to where I should look?