Angier,
Did you take it apart?
One way an intermittent use purposed relay can fail is if it remains
selected for too long, heats up and melts the coil wire insulation which
can then harden and bind the core rod when the relay finally cools
off. If the system is wired as Lancair recommended, this is easily
possible. Say the Master switch is on for extended electrical system
testing, the gear switch is in the up position, the motor power breaker is
pulled but the relay coil power breaker is not and the hydraulic pressure is low
enough that the pressure switch is closed - thus power is applied to the up
relay for a long time eventually destroying it. There will be no
indication at the panel because the transition light is powered from the relay
contactor but the pump power breaker was pulled.
The orientation is not the problem.
Scott
PS My relay coil power is fused and is obtained after the pump breaker so
that pulling the pump breaker removes all electricity from the hydraulic
system.
In a message dated 2/26/2013 7:37:14 P.M. Central Standard Time,
N4ZQ@VERIZON.NET writes:
Gear up
relay failed today...
Fortunately 4ZQ was up on jacks in her hangar at the
time.
Not sure if it was the orientation of the relays or simply age.
In
any event, new relays will be installed in the morning and their orientation
will be reversed.
Angier Ames
N4ZQ
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