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| 2/7/2014 8:51 AM | |
Joined: 3/17/2013 Last visit: 4/28/2025 Posts: 481 Rating:
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Hi Netto As far as drive is considered it's just an alarm and should not cause any trip. Does this happen during machine speed setpoint change or all off a sudden while motor running? Secondly in the PCS7 MOTOR block QALM should not trip the machine. QBAD or FB_Flt for more than set time (default 5 secs) shall cause the trip. Can you send the PCS7 motor block CFC snapshot Regards, Vijay |
| 2/10/2014 11:59 AM | |
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Posts: 7 Rating:
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Hello Vijay; Thank you very much for the information. This Alarm is not comming during any setpoint change, It is comming just like that. Normally it happens in the night and at the time of the alarm, the motor must be running in the same rpm (350 rpm/ 91.3 Hz) continuosly for 2 to 10 hrs. Please find attached the screen shot of the CFC. Currenlty we put a 2 sec delay timer for the QALARM output to bypass these spikes. We also noticed most of the times, the QCOMP also going high (0 to 1) ,like 2 minutes before the QALARM . Regards Netto |
| 2/10/2014 12:56 PM | |
Joined: 4/23/2010 Last visit: 11/23/2024 Posts: 8092 Rating:
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Have you monitored the input supply conditions of drive? Since the problem is only faced during 6.00 to 9.00 PM, it could be related to input supply, might be if you could monitor & compare those readings with day time supply readings. Just have a look. |
| 2/10/2014 1:10 PM | |
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Posts: 7 Rating:
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Thank you! We also suspect this could be from the supply,but we dont have any devices for continuous monitoring/logging the input supply. I have a couple of more questions, Will the supply variation trigger this alarm? If this is from the supply, how can we avoid this? If this is from the supply, can we ignore this Alarm?
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| 2/10/2014 1:24 PM | |
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Joined: 4/23/2010 Last visit: 11/23/2024 Posts: 8092 Rating:
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Yes, this could be one of the reason. If supply voltage varies or rises to the its upper limit, it could cause DC link voltage to rise nearer to its upper limit. Since MM440 doesnot monitor input supply condition, this Vdc _max controller feature comes in the picture. You can monitor the grid voltage which shall give you rough idea about the supply voltage variations. Depending upon the voltage variation levels, suitable equipment can be selected e.g.isolation transformer or servo controlled voltage transformer, etc. |
| 3/6/2014 8:46 AM | |
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Joined: 3/17/2013 Last visit: 4/28/2025 Posts: 481 Rating:
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Hi If QAlarm is set from only drive alarm bit but not from Fault/trip status then it need not be connected as a III input the OR gate. Normally it shall be from QFault. Did it help after Inserting timer Regards, Naga |
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