Dear all,

I have a problem with the external SSI encoder that is main synchronous axis (leading value) for the two following axes.

The problem is that the actual velocity jumps very high for a moment (~1ms) from a value of 240 deg/sek to --359758deg/sec always in the same position. I have no problem with the actual position.

This big negative velocity value changes the extrapolated position and velocity as shown in the pictures. I tried using velocity filters without success. I cannot use tolerance band width because of the high difference in actual velocity.

Have anyone faced the same problem?

Best regards

Hello Kokabt,

we need more information to be able to help you: Template for the new topics

- TIA Version : V18

- Service pack and update : 

- Hardware Modules numbers :
PLC - 6ES7 518-4TP00-0AB0 Fv3.0; 
TM PosInput 2 6ES7 551-1AB00-0AB0 fv.1.3.1;
Abs. encoder. MHAP 200 B5 Z100 SG17N U8192D;
CU320-2 PN with 2 MOMO 

- The desired application :

Two MOMO drives (servo and linear motor) needs to follow the main axis (abs. external encoder). The synchronisation is done with GearinPos and Cam in the T-PLC.

- The Problems (Bugs) : The external abs SSI encoder that is connected to the TM posinput 2 module in one position (always the same position like shown on the pictures) gives verry high negative velocity that acts on the extrapolated velocity and position value. This causes the two followung drives in this point act with velocity limits in oposite direction...

- Expected causes of the Problem :

And of course there are no jerks on shaft physically

Is there identical encoder to be replaced and checked whether a culprit the encoder itself or smth else e.g. software, FW?

It can be wrong type of encoder or its settings, though.

Moderator: such kind of topics basically rather closer to Sinamisc vilage than TIA portal one. In Sinamics vilage reside much more people connected with drives, encoders,etc.