TM 55-4920-429-13
4-19. Circuit Card Replacement.
a.
b.
c.
d.
f.
g.
Remove the panel from the case (para 4-15).
(See fig. 5-3.) Remove the two screws (21) securing the retainer (22) to the card cage (30).
Remove card (25 or 26) from receptacle by pulling the card straight out.
Install replacement card in the receptacle, components towards panel.
Align the cards and install the channel and rubber.
Install the panel in the case (para 4-25).
Perform the final test (para 4-26).
4-20. Replacement of Panel Component (CRC).
a.
b.
c.
a’.
m.
(See fig. 5-3.) Remove the panel from the case (para 4-15).
If needed for access, remove the card cage (para 4-17).
Tag and disconnect the wires.
For a meter, remove the attaching hardware and remove the component.
For a rotary switch, loosen the set screws and remove the knob.
For an indicator, remove the lens and lamp.
For a switch, indicator, circuit breaker, or relay, remove the nut and remove the component.
Position the replacement part in the panel.
For a switch, indicator, circuit breaker, or relay, install the nut.
For an indicator, install the lamp and lens.
For a rotary switch, position the knob and tighten two set screws.
For a meter, install the attaching hardware.
Connect the wires to the terminals. (See wiring diagram, FO-22.) Remove the tags.
n. If it was removed, install the card cage (para 4-22).
o. Install the panel in the case (para 4-25).
p. Perform the final test (para 4-26).
4-21. Replacement of Power Supply or Transformer (CRC).
a.
b.
c.
d.
e.
g.
(See fig. 5-2.) Remove the panel from the case (para 4-15).
Tag and disconnect the wires.
Remove the attaching hardware and remove the power supply or transformer.
Position the replacement part on the assembly. Install the attaching hardware.
Connect the wires. (See wiring diagram, FO-22.) Remove the tags.
Perform the final test (para 4-26). Adjust the power supply (para 4-23).
Install the panel in the case (para 4-25).
4-5
