text: <s>[INST] Powerflex 755 Speed Trim Follower Hi everyone, actually I have the following drive configuration: There are 2 Permanent Magnet motors driving the anvil roll – one on the drive side and one on the non-drive side. The motors are sized at 76.28 kW each (152.56 kW combined). Each anvil motor is controlled by a 302 Amp PowerFlex755 drive – three phase 480VAC fed. Each drive has a 5.3 ohm 22kW dynamic braking resistor connected to it. Only one motor has an encoder on it – the drive side motor (master). The feedback from this encoder goes to the drive panel on the 3rd floor and is split to 2 signal converters. The signal converters output are wired to each drive's Dual Encoder module. The drive side roll runs in Speed Regulation mode with a speed reference passed from the machine Webformer section. The non-drive side roll runs in Torque Regulation with Torque Reference Setpoint set by the drive side Limited Torque Reference feedback. I would like to know the list of parameters to change and the required wiring (if required) to change this configuration to Speed Trim Follower because what we are seeing is that normally one of the drives is managing the major part of the torque so the load sharing system is not working properly. I need to know in detail about the parameters for passing the current Master torque to slave and the required for the slave to compare this value with its current torque and use the error to apply the speed trim. I hope this explanation is clear and thanks in advantage. [/INST] EDIT: removed external formatting -FL Hello, there is some conceptual guidance on how to apply a Speed Trim Follower scheme with AC drives via the following document: https://literature.rockwellautomation.com/idc/groups/literature/documents/wp/drives-wp001_-en-p.pdf This other technote includes a document that goes a bit further highlighting the challenges ahead based on the block diagram of a PowerFlex 700VC drive. There is mention of the Process PI Trim to be required to accomplish this scheme. https://rockwellautomation.custhelp.com/app/answers/answer_view/a_id/516124 I think the way forward would be to understand how this is done on the PF700VC and try to extrapolate or correlate those key block path diagrams from the PF700VC to the ones in the PowerFlex 755. The Reference Manual for the PF755 includes some detailed information at block diagram level as well. https://literature.rockwellautomation.com/idc/groups/literature/documents/rm/750-rm002_-en-p.pdf The other challenge, once the key parameters are identified will be to pass that information from the master drive to the follower(s), possibly by mapping those key parameters to analogue signals and wiring those accordingly. I am leaving an open door here to see if there is anyone on this audience that may have used this concept within a real drive system application and would like to add some advice on what could be a challenging, but very interesting application. \\n </s>