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3-55. If a relay is hermetically sealed with an
opaque cover, which of the following
methods should be used to determine
whether the relay is operating?
1. Shake the relay and listen for loose
parts
2. Place your finger on the cover and
feel the relay contact movement
3. Remove the cover and visually
observe the relay contacts when the
relay is activated
4. Activate the relay and observe
whether a metal object is attracted by
the magnetic field
3-56. If a relay is NOT operating properly,
which of the following items need NOT
be checked?
1. The armature resistance
2. The terminal leads
3. The contact surfaces
4. The contact spacing
3-57. What should be used to clean the
contacts of a relay?
1. Sandpaper
2. Emery cloth
3. A jeweler's file
4. A burnishing tool
3-58. What should be used to adjust contact
clearances on a relay?
1. A point bender
2. A burnishing tool
3. A pair of pliers
4. A pair of hemostats