Warner Electric AT Brakes - Manual (Page 5)

5 Warner Electric • 800-825-9050 819-0334
AT Brake Troubleshooting Guide
If performance problems are present after carefully following the instructions in this manual, use the
following check list.
Symptom Check
Problem Possible Causes
Clutch Rotor will not move or • Coil Resistance
engage when power is applied Coil may be open. See Chart 1.
to the coil • Power Supply
Assure proper DC voltage is being delivered to the brake
• Airgap
If greater than .050" around entire periphery, reset Autogap.
• Autogap
Assure that brake armature is free to move on hub spline and releases approxi-
mately .050" when pressure is removed.
Vibration • Runout
Assure that shaft on which the clutch is mounted doesn't have excessive runout.
• Shaft Engagement
Assure adequate shaft length and diameter engagement in the hub.
Excessive Start or Stop Times • Power Supply
Assure proper DC voltage is being delivered to the brake.
• Adequate Burnishing
Unit must be run and cycled a few times to achieve full rated torque.
• Friction Surfaces
Replacement may be required.
• Friction Surfaces
Installation of replacement friction material or armature segments may be
incorrect and not allow full contact.
Clutch/Brake Coil Approx. Coil
Size Voltage Resistance (Ohms)
25 6 1.4
25 24 20.6
25 90 290
55 6 1.2
55 24 19.6
55 90 230
115 6 1.0
115 24 16.5
115 90 182
Chart 1