We use an additional clamping device on a vertical axis driven by a servo motor for safety.
Is it possible to test this device using a brake test on an “external brake” (f.e. similar to functional block “MC_BR_BrakeControl”) ?
Can anyone help Manfred?
Hello,
i know this use Case with the external Brake for Safety reasons, but i did not yet implemented a Test of this Brake. And even not normal Brake tests, so i am not an Expert in this. But i try to give some hints.
I can tell that the MappMotion successor of MC_BR_BrakeControl could be MC_BR_BrakeTest_AcpAx. But this Functionblock has far less input Settings. And it seams only controling the Internal Brake.
Here is some Documentation about Brake test in the ACOPOS Firmware in general. I did not find any indication of having a switch to an external brake.
AS-Help Brake Test
If nobody here in the community has an answer i would recommend to ask local B&R Support to validate these findings.
A coustom implementation of a Brake test for an external Brake can be build with these functionblocks and a Step-Sequence following the concept of the internal brake test.
-
Reading the current Position of the Axis and make a cyclic check for the limit-Values. If exceded abort all operation.
MC_BR_ReadCyclicPosition mcVALUE_ACTUAL -
Have the Safety Brake closed and PowerOn the Axis in Standstill.
Check that the Control-Loop does not act to much against the closed brake.
(if this is an issue, you have to disable Position control before PowerOn but this would be additional effort. It is easyier if Position Control can stay enabled at this point) -
Use the Torque Control Function of the Axis to move against the Closed Safety Brake. Read Values via Functionblocks and Check the movement Limits.
MC_ReadActualTorque
MC_BR_TorqueControl -
Disable Axis Close Motor Brake , return to normal operation which could be opening safety Brake.
I hope you can find a good solution for your application.
Greetings
Michael