Profibus mismatch of safety status word in PLC

Dear Experts,

I am working on S7 1500 PLC and I have a safety drive to which PLC is connected. Uponpower upthe safety drive has STO activated and hence internal event is also high for safety reasons. This has to be acknowledged to start to operate.

On the drive side I am seeing that on power up,  STO bit on the status word is high.

On the PLC side, the STO bit on the status word is not high.

For the further debug, we used the wireshark to see the communication between drive and plc. The drive sends the status word as 0081h (screenshot can be seen in the attahced pdf).  But the PLC displays as 0000 h .

PS: 0081h corresponds to STO and internal event activated.

My question is why I am not seeing the same safety status word as drive sends on the PLC side upon powerup ? 

After the error is acknowledged the status word on PLC and drive are same. This problem happens in the beginning.

Your telegram may not be configured properly to receive data in the way your logic is expecting.

Check the PLC telegram I/O addresses used, especially the Inputs Which word is the safety status word relative to the start of the telegram?  Is the logic using the correct input word offset?

SiemensPLC_Learner

Dear Experts,

I am working on S7 1500 PLC and I have a safety drive to which PLC is connected. Uponpower upthe safety drive has STO activated and hence internal event is also high for safety reasons. This has to be acknowledged to start to operate.

On the drive side I am seeing that on power up,  STO bit on the status word is high.

On the PLC side, the STO bit on the status word is not high.

For the further debug, we used the wireshark to see the communication between drive and plc. The drive sends the status word as 0081h (screenshot can be seen in the attahced pdf).  But the PLC displays as 0000 h .

PS: 0081h corresponds to STO and internal event activated.

My question is why I am not seeing the same safety status word as drive sends on the PLC side upon powerup ? 

After the error is acknowledged the status word on PLC and drive are same. This problem happens in the beginning.

I guess that your servodrive is from LinMot?

Because serie C12xx isn´t with Profibus connection or do you have some especially type?

I use few LinMot servodrives with linear actuator but don´t used communication of your type.

J.