e. Clutch/Brake Assembly Replacement.
(1)
Turn off power to the SFD.
(2)
Remove the rear cover, following the instructions in paragraph 3-6a (2),
above.
(3) The clutch/brake wiring is connected both to a header mounted to the
interface board and to the ac-input-terminal block in the rear corner of the SFD chassis.
Carefully cut the cable ties securing the wiring.
(4) Remove the white wire from terminal 1 of header J6 and the black wire
from terminal 3. Remove the red wire from terminal 4 of the ac-input terminal block.
(5) Manually rotate the shaft linking the stepper motor to the clutch/brake
assembly until the setscrews on the couplings are visible.
(6) Loosen the setscrews on the motor and clutch/brake sides of the shaft to
allow axial movement, then slide the shaft toward the motor so the input shaft of the
clutch/brake is disengaged from the coupling.
(7)
Loosen the tensioning pulley above the clutch/brake assembly.
(8)
Remove the four screws securing the clutch/brake assembly to the
chassis.
(9) Disengage the pulley from the cogged belt and lift out the assembly.
Observe the caution note in the previous subparagraph.
(10) Note the pulley is installed on the shaft extending from the output side of
the assembly. Remove the pulley and save it for installation on the replacement
clutch/brake-output shaft. When re-installing, tighten one setscrew into the keyway to
help prevent loosening.
(11) Install the new clutch/brake assembly following the above procedure in
reverse.
(12) Re-tension the belt so it does not deflect more than 3/8-inch (9mm).
(13) Tighten the tensioning pulley.
(14) Reconnect the wiring to the header and terminal block. Refer to step (4)
for connection points with regard to color coding. Secure the harness(es) with (a) new
cable tie(s).
MD0351
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