FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 11. Aircraft Electrical Systems | 4. Inspection of Circuit-Protection Devices | 11-56. Operating Conditions for Switches and Relays
AC 43.13-1B CHG 1
9/27/01
insulation of the electrically “live” compo-
nents) is especially vulnerable to catastrophic
failure as a result of overtorquing.
(1) When replacing relays in alternating
current (ac) applications, it is essential to
maintain proper phase sequencing. For any
application involving plug-in relays, proper
engagement of their retaining mechanism is
vital.
(2) The proximity of certain magneti-
cally permanent, magnet assisted, coil operated
relays may cause them to have an impact on
each other. Any manufacturer’s recommenda-
tions or precautions must be closely followed.
11-49. LOAD CONSIDERATIONS.
When switches or relays are to be used in ap-
plications where current or voltage is substan-
tially lower than rated conditions, additional
intermediate testing should be performed to
ensure reliable operation. Contact the manu-
facturer on applications different from the
rated conditions.
11-50. OPERATING CONDITIONS FOR
SWITCHES AND RELAYS. Switches and
relays should be compared to their specifica-
tion rating to ensure that all contacts are made
properly under all conditions of operation, in-
cluding vibration equivalent to that in the area
of the aircraft in which the switch or relay is to
be installed.
11-57.11-65. [RESERVED.]
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