AC800M BMI problem with group starting of on drive
I have got the situation that from time to time one drive is not starting with BMI GROUP sequence start (let say that 1 per 10 starts is like that). Control module for this drive is MOT1_VVVF.
This drive is starting in step 12, there is no error on faceplate of this drive so in my opinion it should start. There is also no alarm in alarm list.
What is more as you may see in the picture I am not able to click on Start button at group faceplate. The only way I am able to run it is by clicking on Hold button and after that on Start button.
More details you may see in the picture below.
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The Group start is a pulse, and i know the same behaviour you describe can happen if some Interlock is active while the Start Pulse is coming, for example some Feedback Signal from the Previous Drive is used as Interlock and sometimes is not yet ok when the Group Step is executed.
So could there be any Interlock active during startup (which is already ok again at the time of the screenshot)?
Have your group and the step 12 motor faceplate open.
watch for the motor faceplate to try for a start when the group faceplate is on step 12.
If the motor is not starting it might me a PD,IA interlocks.
If the motor is starting and dropping of without any alarm it might be because of FB1,FB2 interlocks.
Check you OPC server to have a string update rate of 1000 ms as recomended by BMI library,if not the case like this will be hard to troubleshoot.