Sample blocks for torque control for CU240-2PN

Technology Team

Hello,

the attached graphic from STARTER shows the relationship of p1511, p1512 and p1503 pretty good.

You can see, that p1503 takes only effect when the torque control is active or torque setpoint is selected over p1501. The additional torque in p1511/p1512 takes effect in speed control too.
All values send from the PLC to the drive are percentage values based on the corresponding reference value of the SINAMICS, in case of torque p2003 “Reference torque”
I think the easiest way would be to use p1503 in the telegram to send a torque setpoint. You just have to use the same value like p2003 in the PLC to convert your torque setpoint into a percentage value.

To jog the drive in speed control you have to change the operating mode back to speed control. The article you have mentioned is for old control units without “-2”. In the new ones like you are using CU240E-2PN this parameter is not available. Here are the parameter p1055 and p1056 for jogging.
There are two possibilities how to realize to jump between the two operating modes.
First you can use p1501 to switch between a torque and a speed setpoint. In this case p1300 is “speed control” and you just take the torque setpoint of p1503 if p1501=1. If p1501=0 the drive runs with the speed setpoint i.e. the jog setpoint.
The second way would be to use two different drive datasets, one with torque control and the second one with speed control. You can change between the two datasets with help of a digital input.

In these cases you have a real torque control, so if you have a sudden load drop your motor can accelerate up to maximum speed if the torque setpoint remains the same. A possibility to prevent this is using an overdriven speed controller. Here you are limiting the torque limitations of your drive according to your speed setpoint and you just send a speed setpoint which is a little bit higher than your real operating point. In this case the motor is operated on the torque limit all the time but it just speeds up to the slightly higher speed setpoint in case of a load drop.

 Dear Team,

Can you please attach some sample blocks for torque control for CU240-2PN ?

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Split from Torque Control of G120.

Hello,

You have written:

"In these cases you have a real torque control, so if you have a sudden load drop your motor can accelerate up to maximum speed if the torque setpoint remains the same. A possibility to prevent this is using an overdriven speed controller. Here you are limiting the torque limitations of your drive according to your speed setpoint and you just send a speed setpoint which is a little bit higher than your real operating point. In this case the motor is operated on the torque limit all the time but it just speeds up to the slightly higher speed setpoint in case of a load drop."

I don't know how to program the overdriven speed controller so that this speed limitation works.
What parameters are you referring to?
Thank you

They mean running it in speed control with dynamic torque limits as needed for the control. The speed command will be a speed setpoint that is high enough to reach the controlled torque limit in all required situations.

For example, let's say you need 100N-m of torque which will run around 1600 rpm with the given load.  Set the speed setpoint @ 2000 rpm, and adjust torque limit (or scaling factors) to limit torque to 100N-m.

Drive navigator can get you to the torque limits and their scaling factors, and also hovering over over the displayed values shows the associated parameters.

Bild to rotate

Hello,

You have written:

"In these cases you have a real torque control, so if you have a sudden load drop your motor can accelerate up to maximum speed if the torque setpoint remains the same. A possibility to prevent this is using an overdriven speed controller. Here you are limiting the torque limitations of your drive according to your speed setpoint and you just send a speed setpoint which is a little bit higher than your real operating point. In this case the motor is operated on the torque limit all the time but it just speeds up to the slightly higher speed setpoint in case of a load drop."

I don't know how to program the overdriven speed controller so that this speed limitation works.
What parameters are you referring to?
Thank you