Multi-load positioning using the same TO

Hello everyone,

I am new to the forum and have a question regarding running multiple encoders with the same drive.

How can I dynamically switch between different encoders for servo positioning, and also adjust the drive’s Kv value accordingly?

Best regards,
MQ

AutoGen_7982354

Hello everyone,

I am new to the forum and have a question regarding running multiple encoders with the same drive.

How can I dynamically switch between different encoders for servo positioning, and also adjust the drive’s Kv value accordingly?

Best regards,
MQ

 

The immediate reason for your request is not apparent at the moment. Are looking for a bumpless transfer between the encoders? You did not mention which version of motion control you use or which CPU. Very little information makes for volunteers playing guessing games.

You could link the 'encoder' feedback to a datablock instead of the actual encoder. The datablock can be populated in the Preservo OB as needed.

For the Kv value.. The MC_WriteParam instruction can modify this value BUT the axis cannot be enabled. This creates a problem for bumpless operation.

You could create a support request with Siemens to discuss your options for your specific application.

Thanks for the tips — much appreciated! Like I mentioned, I’m quite new to forums, so I really value the guidance.

To clarify a bit: this post is mostly educational for me right now. I’m exploring the idea of building a servohydraulic pump system that can control 3 different actuators— ideally using a single servo drive and switching between actuators.

My initial thought was to go with the G120C due to cost, but after doing some reading, I’m considering whether an S120 with different DCCs would be a more suitable path.

The PLC I had in mind is a CPU 1511TF-1 PN, and I’d likely useTechnology Objects version 4.0 or 6.0 depending on compatibility.

At this stage, I’m just trying to understand whether such a configuration is technically feasible — especially in terms of switching feedback (encoder) sources and coordinating bumpless transfer between axes, if possible.

Thanks again for taking the time to reply — I really appreciate it!

MQ

Possibly your case can be handled more easily. It is possible to configure multiple motion controls that uses the same 'output'. There should be an FAQ about this topic that was done long ago, but I cannot seem to find it now. There is reference of something in the S7-1200 Motion Control Function Manual.

LINK: SIMATIC STEP 7 S7-1200 Motion Control V6.0 to V8.0 in the TIA Portal as of V17

Focus on the mechanism of exchanging Axis with each other. The concept may be for PTO on an S7-1200, but the basis principles would work for your situation too.

~

Bonus link: SIMATIC S7-1500 – All about Motion control