Hoist mechanical brake

What does 22 mean?

This warning/alarm indicates an issue with the hoist mechanical brake control. A value of '0' means the torque reference was not reached before the timeout set by parameter 2-27 Torque Ramp Up Time. A value of '1' means the expected brake feedback was not received before the timeout set by parameter 2-23 Activate Brake Delay or parameter 2-25 Brake Release Time.

• Mechanical brake pads are worn, misaligned, or sticky, preventing timely full disengagement during hoist operation.
• Brake control circuit malfunction, such as a faulty brake relay (e.g., K301) or insufficient current to the brake solenoid.
• Motor's actual torque output is insufficient to overcome the load and brake friction within the time set by P2-27.
• Parameter P2-27 (Torque Ramp Up Time) is set too short, not allowing enough time for the brake to fully release.
• Brake solenoid coil resistance is out of specification, leading to weak braking force or delayed response.

Click steps to track your progress.

1. 1

   Measure the resistance across the brake solenoid terminals (e.g., X1:1 and X1:2) and compare it to manufacturer specifications (e.g., 20 Ohms).

2. 2

   Visually inspect the mechanical brake assembly, pads, and linkage for wear, scoring, or obstructions.

3. 3

   Increase the value of parameter P2-27 (Torque Ramp Up Time) by increments of 50ms to allow more time for brake release.

4. 4

   Verify the drive's actual output current to the motor using an external current clamp meter during brake release (e.g., phase A1, A2, or A3).

5. 5

   Check the status of the brake control relay (e.g., internal relay K301) for proper switching operation (audible click, coil voltage).

6. 6

   Adjust parameter P6-20 (Min Torque Ref) to ensure adequate motor torque is commanded during the brake release sequence.