Hello everyone,

I'm asking for your help with some information.

I have a small project with a motor for a fan and a motor driving a chain.

For this, I'm using two G120 variable frequency drives (VFDs).

I've never worked with Siemens VFDs before.

After looking at some documentation and various videos, I can't determine the best control option.

I would like to control it with a speed command, and I would also like to be able to adjust the acceleration and deceleration ramps from my HMI. I also want to retrieve speed and current measurements.

I was thinking of using Telegram 20 and a SpeedAxis technology object.

However, I don't know which Motion Control instructions to use.

Do you have any advice to guide me?

Thank you in advance.

Hi

Motion Control is dedicated for servo control - with encoders, postitioning, gears and cams etc.. 
Of course it's possibile to control G120 using motion control - but there will be a lot of configuration and parameters, which you will not use but they will make it's more complicated.

In your case I'd rather use SINA_SPEED - to control the drive (start + speed + Actual speed readback) and SINA_PARA to change ramps and current read.

You can find more information here:

https://www.youtube.com/watch?v=ZeBK-DFRYI8

https://publikacje.siemens-info.com/pdf/675/SIMATIC%20S7%20+%20TIA%20Function%20blocks.pdf

Best regards,

Rafał

Hello,

I will follow your advice and look at the links you provided.

Later, I will try to learn more about motion control.

Thank you for your advice.

Sincerely,

Florian

Hello, I followed your advice and am using Sina_Speed_TLG20, which allows me to control my motor with speed setpoint, speed reading, and current reading.

It works very well.

However, I can't find the Sina_Para documentation to change the acceleration and deceleration ramp parameters.

Is it possible to do this? Or would it be better to create a "Ramp" function block and adjust the speed setpoint?

Sincerely,

Florian

Using SINA_PARA which is described in documentation I sent before you can change any parameter of G120.

Here you have the film about how to work with the function.

https://www.youtube.com/watch?v=RCixA4w9eIo

You need to change parameters number: 1120 and 1121 I guess (you can check it in the manual of control unit you use)