Bill,
 
I am unable to attend.  As far as functional life testing goes, we maintain our LTC’s on a regular basis.   Contact wear, contact pressure contact alignment and timing are the usual steps.  We also, where possible view the operation of the LTC to assure it’s switching properly.  I don’t think we monitor motor current unless it’s part of an on-line monitoring system.
 
I don’t recall ever removing an LTC from service due to end of functional life.  We’re repaired and/or replaced but usually due to damage.
 
Hope this helps,
 
Rowland James