Warner Electric Preassembled Clutch_Brake Module - Manual (Page 5)

5 Warner Electric • 800-825-9050 819-0343
Trouble Shooting - Mechanical
A likely mechanical cause for a clutch or brake
not engaging when DC power is applied is that
the airgap between the friction faces is too
large. When power is applied to an Electro-mag-
netic clutch/brake, the unit magnetically clamps
the friction faces together.
An airgap that is too large can keep the unit
from clamping together. Sometimes this airgap,
when set at the factory can shift during ship-
ment or installation.
To reset the airgap, you will need to access the
armatures. There are gaps between the fins on
the housing on 1/3 of the unit circumference.
Figure 7
When looking through one of these gaps, you
will see the fan on the clutch rotor. In that fan,
there is a 1/2" x 1" window.
Figure 8
It is possible to look inside the unit and see the
armatures by looking through this window.
When looking into the window, you will be look-
ing between the two armatures of a clutch/brake
unit.
Clutch/Brake
Control
AC
Clutch
Brake
White
Black
Red
Red
Black
Black
DC
DC
Voltage
Voltage
Voltage
Start-Up
With the motor at rest, check the following:
A. Spin the output shaft by hand to ensure that
it turns freely. The bearings should be quiet
and the armatures should not drag.
B. With full voltage applied to the clutch or
brake, switch back and forth between the
clutch and brake and observe the armatures
(plates) through the vent holes and opening in
the fan. They should move back and forth
approximately 1/32" when switched. Turn
the output shaft as you check to be sure that
the armatures fully engage 360 degrees.
Trouble Shooting - Electrical
If a clutch or brake or clutch/brake will not
engage, review wiring, switching, and connec-
tions.
1. Using a multimeter, confirm that DC voltage is
reaching the lead wires when it should be
and that the coil resistance is correct. (See
Electrical Coil Data)
2. Visually inspect to ensure that the lead wires
are not split or cut.
Please refer to the following figure for the proper
UniModule electrical connections. Clutch leads
are identified with a white insulator sleeve.
Brake leads have a black insulator sleeve.