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Date: Wed, 27 Nov 2013 10:52:40 -0500
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Subject: Diode snubbers on solenoids
From: Jack Morgan <jmorgan1023@comcast.net>
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References: <listdigest-6615325@logan.com>

All,

Elsewhere on the list we are having an, I hope, interesting discussion =
on protecting switch/relay contacts with snubbers. This separate note is =
for the starter and master solenoids which are additionally used on the =
gear pumps by Lancair.

You builders probably received a snubber diode packaged with your =
starter/mag key switch. This is the certified practice to protect the =
switch from the relatively large energy the switch sees when the starter =
solenoid is de-activited. This is a time proven method of protecting =
against this failure mode. For those of you with the conventional diode =
in place, rest easy as it is the proven solution. The starter solenoid =
is more highly stressed when it breaks the starter current than the =
hydraulic solenoid is when it breaks the pump current so rest assured =
again that a conventional diode is safe here also.

This note is just to insure we don't get lost in the weeds created by =
the far more complex subject of protecting smaller relays.

As always... hope this clarifies and helps. Fly safe.

Jack Morgan=