Troubleshooting - Yale 524150797 Maintenance Manual

Troubleshooting

PROBLEM
Brake does not release.
Brake does not hold truck loaded to
capacity on 10% grade.
6
Troubleshooting
POSSIBLE CAUSE
Key switch is in the OFF position.
Battery is not connected or prop-
erly charged.
Handle is not in the BRAKE OFF
position.
Control handle arm prox switch is
out of adjustment/damaged.
Brake coil open circuit.
Brake coil has shorted to frame or
between the windings.
Incorrect or no voltage supplied to
brake.
Debris pollution of residual gap.
Air gap is too large.
Friction disk is too worn.
Brake hub damaged.
1800 YRM 1505
PROCEDURE OR ACTION
Turn key switch to the ON position.
Connect or clean battery connec-
tions. Charge if necessary.
Move the handle to the BRAKE
OFF position.
Adjust/replace control handle arm
prox switch. See the section Elec-
trical System 2200YRM1508.
Measure coil resistance. Refer to
Brake Check in this section. If re-
sistance is above specification, re-
place the brake assembly.
Measure coil resistance. Refer to
Brake Check in this section. If re-
sistance is below specification, re-
place the brake assembly. Check
coil for short to frame using an
ohmmeter. If shorted to frame, re-
place the brake assembly.
Measure voltage to brake using a
voltmeter. If voltage is not 24 VDC
±10%, troubleshoot brake wiring.
Troubleshoot electrical system and
controller.
Clean air gap. Ensure that residual
gap returns to 0-0.06mm.
Replace the brake assembly.
Replace the brake assembly.
Replace brake and hub assembly.