Motor Brake Monitoring
In accordance with EN81-20 the drive can be used to monitor and verify (using Brake micro switches) the mechanical brake dropping mechanism after each brake release/apply (Relay 2 of the drive as default), and if verification fails then the drive will trip and prevent the drive reacting to any further run commands, once the trip occurs then it can only be reset by a “competent person“ and not by a normal trip reset or power cycle.
The brake micro switches can be connected to either the Universal Encoder Module or directly to the drive terminals as illustrated in the diagram below, noting that the function is enabled using parameter P5-04.
When the function (Motor brake monitoring) is enabled, the drive will monitor the chosen terminals as per set in P5-04 and check that each time the brake is commanded to open/close the micro-switches change to the correct state within a set time (P5-05), if the state is incorrect then the drive will display the warning message "bF-Err", reset and have another attempt, if after the number of attempts (as set in P5-06) the brake micro switches are indicating the incorrect state then the drive will permanently show the error message "bF-Loc".
Before the lift is put into service, test runs should be performed to ensure that the function works as expected.
In the instance of the permanent error message "bF-Loc" being shown, then it can be cleared as follows:
Disable drive.
Set P5-04 to Off.
Press Mode button.
Set P5-04 back to the required monitoring terminal as per set in (P5-04).
Once the relevant parameters have been programmed (as detailed above) then the “Brake release monitoring” function should be verified for correct operation, this can be carried out by exercising the micro switches/monitoring input (during a low speed run) to simulate the brake not releasing/closing and checking that the "bF-Err" / "bF-Loc" error message/s is shown.
Parameter Number | Parameter Name | Units | Default | Available Settings | Access | Change During Run | Scaling | Size (Bytes) | CAN Register | CAN Sub Index | Modbus Register |
|---|---|---|---|---|---|---|---|---|---|---|---|
P5-04 | Brake Release Monitoring Enable | N/A | 0: Function Off | 0 ... 2 | RW | Y | N/A | 1 | 21F8h | 0 | 504 |
P5-05 | Brake Release Monitoring Time | sec | 0.5s | 0.1 ... 5.0s | RW | Y | 1 = 0.1 s | 1 | 21F9h | 0 | 505 |
P5-06 | Brake Release Number of Errors Before Lockout | N/A | 0 | 0 ... 5 | RW | Y | N/A | 1 | 21FAh | 0 | 506 |
P5-07 | Brake Release Monitoring Errors | N/A | 0 | 0 ... 65535 | RO | N | N/A | 2 | 21FBh | 0 | 507 |
Setting | Function |
|---|---|
0 (Function Disabled) | Motor Brake Release Monitoring Disabled |
1 | Motor Brake Release Monitoring Enabled and monitored via Daux 1 Input and Daux 2 Input on the Universal Encoder Module with 2 N/C contacts. |
2 | Motor Brake Release Monitoring Enabled and monitored via Digital Inputs DI5 and DI6 providing that P1-02 is set to Macro 8 and Digital input DI7 if P1-02 is set to 9. |
If the monitoring terminal has not changed state in this time (since the brake has been released by relay 2 of the drive) then the drive will trip “bF-Err" or “bF-LoC" (if number of attempts as set in P5-06 has been met)
The drive will automatically try to clear the “bF-Err” at 1.5 second intervals for the number of times set, after each attempt the travel sequence will restart, once the number of brake release monitoring errors has reached the number set in this parameter a permanent trip "bF-LoC" will be displayed.
Total number of “bF-Err" trips since the drive was installed.
The counter can be reset when default the drive parameters.