PowerFlex 525 Status Bits

[mylespetro]

Hey everyone,

Currently working on a project to replace some old AB 1336 and PowerFlex 4 drives with 525s, as well as the existing SLC 5/04 with a CompactLogix. The existing program has an alarms routine that reports certain VFD status bits back to the DCS, but the default module I/O in Logix doesn't exactly have what I need. I know there's the VFD:I.DriveStatus available by default, but that only has 5 bits (Running, Forward, Accelerating, Decelerating, and SafetyActive).

The original status bits that would alarm back are:

1. Drive Current Limit (525 Fault Code: F012)
2. Motor Current Limit (525 Fault Code: F007)
3. Motor Stalled (525 Fault Code: F006)
4. Ground Fault (525 Fault Code: F013)

I know how to set these in the drive parameters, but is there a simple way to bring each of these faults out as a single bit to use in the program? I feel like the answer to this is very obvious, but most of my experience is with the 750 series, and the module-specific data available with those seems to be a bit more in-depth.

Thanks!

 

[dmroeder]

I think you can add the fault code as an additional data link, this would be a numerical value representing the fault code.

Open the drive properties in the tree, on the General tab, click Change. You will see the ability to select different parameters for "Input Data".

 

[mylespetro]

I think you can add the fault code as an additional data link, this would be a numerical value representing the fault code.

Open the drive properties in the tree, on the General tab, click Change. You will see the ability to select different parameters for "Input Data".

Duh, that was easy, I'll take a look at the available parameters.

 

[mylespetro]

So I checked out the available parameters, and DriveStatus2 gets me CurrLimit and MotorOverld, but it doesn't have bits for stall or ground fault. I'm going to keep combing through the parameters and see if I missed something. Thanks for the pointer!

 

[dmroeder]

What if you just pulled Fault code back, then map the fault codes you mentioned to the DCS

If FaultCode = 12, turn on bit to DCS that tells it the drive current limit fault occured.

 

[mylespetro]

What if you just pulled Fault code back, then map the fault codes you mentioned to the DCS

If FaultCode = 12, turn on bit to DCS that tells it the drive current limit fault occured.

I thought about doing something like that, but I was trying to figure out how to show concurrent faults, as I believe the first fault will show up in Fault 1 and then as another comes in it would move to Fault 2, then Fault 3 and so on. I suppose I could do something like putting branches with 3 EQU instructions, with Fault 1/2/3 Code as Source A and 12 as Source B, and if any are true, that would be a current limit fault for example. It would just be nice to have an explicit bit for it so I didn't have to use a workaround.


Thanks again!

 

[mylespetro]

I think I've figured out the best way possible to get the stall/ground fault status to the DCS. My biggest worry was that clearing the fault would leave it in the buffer, so that once it was cleared, the drive would no longer be faulted, but FaultCode1 being equal to 6 (stall) or 13 (ground fault) would make the DCS think that it was still in that state. I found parameter A551, which I can set to clear the buffer when the fault is cleared on the drive, so as long as the fault doesn't reoccur, it will be cleared on the DCS as well.


Screenshot of the logic attached. Not a huge fan of using latches and unlatches, but that's the way the existing PLC program works at the moment and I don't want to mess with it too much.