Powerflex 755 with Safe Speed and Encoder modules

[phuz 2]

We are using a Powerflex 755 with a Safe Speed Module for safe speed limiting and door monitoring. We have a 20-750-ENC-1 which was purchased for this project, but I am seeing in some documentation that a 20-750-DENC-1 (dual encoder) is required for this. We are receiving a feedback fault from the safe speed module which tells me the problem is with the encoder module and I am thinking we have the wrong one. However, while poking around Drive Executive under the Safe Speed module, under Feedback, under Fbk Mode (Parameter #27), I can choose Single or Dual, so I would expect the 20-750-ENC-1 to work. Wrong? Also, we cannot locate any manuals on the encoder modules. Are these available or are they buried in a different manual?

[JeffKiper 9]

I have a job coming up that will require me to use the safe speed as well. From what I found in documentaion the safety category is gong to determine what feedback you use.

[phuz 2]

OK, it turns out we needed the DENC-1 module, which we have acquired and installed. Now the drive is not faulted and showing "READY" but we cannot get the drive to start. We have the SS_IN and SLS_IN on the safe speed module and the module is showing as OK, but it will not start when I activate LogicCommand_Start or Run or Forward, etc. When I had the safe speed module disabled, I could start the drive using the LogicCommand_Start and setting a frequency. Am I missing something now that it's enabled?

[TonyGoody 0]

We are having similar problems with the safe speed option module. Kept getting Fbk1 fault. AB tech support had us switch to the dual encoder board. No change. Did you do anything else to fix your problem?

[Jax1973 0]

Hello All

This question is for the Powerflex 755 as well.

We are wanting to use the safe speed mode option.

But when we select the Ethernet IP option as well it then only permits a selection of Ethernet IP encoders.

So my questions:

1- Does tis mean that using the Ethernet IP option I no longer need the DENC or Universal Feedback device?

2- Where do I find the resolution for these IP encoders?