PF753 and RS5000

About 2 years ago we had some equipment installed that is a compact L32 plc and four PF drives connected with Enet. After installation, we changed the carrier frequency of the drives from 2.0 to 4.0,through the drives'hmi, to get rid of annoying high freq. noise. Works fine.

Fast forward recently a contractor switched off a breaker, killing power to the plc box. Everything came back up ok, but the carrier frequencies went back to original 2.0 setting.

I have little experience in drive commissioning with the RS5000 project (AOP?). If we change a parameter with the drives' hmi, that parameter does or does not get saved in the plc its connected to? I'm assuming that when the plc powered back up, it dumped parameters back to the drive?

Thanks!

It's possible that you have a feature called "Automatic Device Configuration" enabled in this system. When activated, every time you re-energize a drive, the Logix processor compares the programming of the drive to the program it stores in it's memory and over writes whatever is in the drive if it is different. It's a feature used to allow rapid replacement of drives by electricians who know nothing about them or programming them. They can take a brand new drive out of the box, or an unused drive from somewhere else, and simply wire it in. When it comes on-line, the correct programming is uploaded into it automatically.

The one drawback is what you just experienced; if you make changes on the keypad, they are over written the next time power is cycled. Just go on-line with the Ethernet connection and change the programming in the Studio (or Logix) 5000 program, or upload the drive programming into 5000.

Thanks for the reply!

I can't seem to get the drive AOP to open correctly. Attached a screenshot. It is trying to correlate with the drive but won't. I built the database under the 'General' tab, but didn't help.

Seems its asking for a power cycle. PLC or VFD?

All four VFD's give me this same screen. Looks like it needs a 'Power Cycle'. Does this mean each drive, or the plc? Either option will require some shop downtime.