The test plug provides a quick and easy
means of testing drawout case relays or meters
without removing them from their
cases. The test plug is substituted for the
regular connecting plug and there is nothing
to disconnect. The XLA12A enables power
to be applied to the relay from either a separate
source or the source that feeds the
equipment. The XLA13A can only be used
when a separate source of power is available.
To insure low-contact resistance the test
plug contact fingers are silver plated.