The frequent loss of Powerflex 4 and 40's throughout our plant.

Happy New Year ,

We have a number of Powerflex 4's and 40's throughout our plant. We have
had a outrageous number of these drives fail the last 2 years , that really impacts our budget and production. Have any of you experienced a large number
of these drive failures , also ? If so , what have you done to solve this , and if not , what would be your recommendation ? Also , what is your thoughts on the
Powerflex 525 drives ?

Thanks so much in advance,

Do you have line reactors installed in front of the drives? Adequate ventilation?

What do line reactors actually do ? What internally happens to drives without reactors ?

Thanks,

I found this description which seems pretty understandable

http://www.vfds.com/how-line-reactors-will-help-your-vfd

What sizes are your drives. ?

The biggest portion of my day is correcting issues for failing Powerflex 4's. We have many and they have been failing at an incredible rate. The one thing about our failures is that I am in a food facility and so we wash down with high pressure hot water and caustic every single night. <---- This is so much fun. I highly recommend being an automation engineer in these environments! If you ever thought production operators were fun...they have nothing on sanitation. I have been moving all of our panels off the machines and moving them to VFD cabinets on the mezzanine. I am then running Modbus TCP/IP to IDEC FC6A's and having all the drives operated from an HMI. I have also been replacing out the Powerflex's with ABB ACS355's. I have been thinking about switching to the ACS550's because they have a choke built in.

I relate with your feelings though. Other than the big rebuilds, failing VFD's is the basis of my job.

I tried out 25 of the 525's. I have not had a single failure yet (only in for a year and a half to this point) and they are easy to work with. The only reason I went with the ABB's over the 525's was the dealer network in my area, price and the advanced operator panel that explains issues in plain English and not codes (we have Maintenance Technician issues...).

Thaddius

When did this problem start?
Or has this been a problem since the line was installed?

The plant as been there for 10 years and has had issues with drives being short lived. I know there was a lot of Powerflex 4 and 40 drives in 2004 , that had some issues. We have several panels that have drives no bigger than 5 hp. These panels have roughly 17 drives in them. I was wondering if we could install
one large reactor for all 17 drives.

I remember in the late 80's installing ABB SAMI MiniStar drives. As far as I know
most of these drives in this plant are still running . They don't make them like they used to .

Thanks for your input.

Baker in Virginia said:

The plant as been there for 10 years and has had issues with drives being short lived. I know there was a lot of Powerflex 4 and 40 drives in 2004 , that had some issues. We have several panels that have drives no bigger than 5 hp. These panels have roughly 17 drives in them. I was wondering if we could install
one large reactor for all 17 drives.

I remember in the late 80's installing ABB SAMI MiniStar drives. As far as I know
most of these drives in this plant are still running . They don't make them like they used to .

Thanks for your input.

Click to expand...

How big are the panels that have 17 drives? HxWxD... Are there any cooling devices on the panels? I have put line reactors for a whole panel before and it works well. The think I would be worried about is enough air. Even the small drives require a good amount of air to circulate. This is why my drive panels tend to be 24" deep minimum. They are awkward panels but they give enough room for air to circulate.

I've literally installed thousands of PF40's in my time, and haven't had any abnormal failure issues. BUT, we always install them with line and load reactors, regardless of whether they are 2HP or 100HP. The most recent installs have been PF525's and haven't had more than a year or two on them, but so far no issues.

Is it possible that the input power gets removed and re applied before the bus completely discharges? This has been a big issue on drives in general.

Hi,

This issue has been mentioned before on the forum..

http://www.plctalk.net/qanda/showthread.php?t=67658

and

http://www.plctalk.net/qanda/showthread.php?t=25438&highlight=powerflex

We have installed multiple Powerflex 525 drives - no reported problems so far

What is the fault code?

We had this problem a few years ago. It would mainly happen on the weekend at the same time of the day. It turned out that this is when the power co. does something at there switching station. It would also happen on startup of the conveyors after a down day.

We checked our incoming power and found it to be between 526 volts and 529 volts. The power co replaced all 3 of the transformers on the pole and that solved that problem.

There was also a problem A/B had with a manufacturing issue causing faulty inverters a few years ago.

Yep, same thing at our plant. PF40. Fault power supply modules. Replaced bucket loads of modules. Been fine since.

How long ago ? Did Rockwell have a recall on those drives ? I know around 2004 they had some issues .

Thad, +1 for the sanitation statement. I worked in a meat processing facility and we had water issues every day, especially when temperature changes for washdown.

As far as your failing drives, contact the utility company and they will help you monitor incoming voltages. Transients and harmonics from motors starting up can cause all kinds of issues and I would start there.

This can be one of those hard to solve problems, and you should take your time and be methodical.

Another thing I would look at would be how long these drives have been in service. The last year at my old job we had a ton of SEW Eurodrives fail on a VRT Freezer system. They were 8 or 9 years old and had been in a poorly maintained cabinet. This thing was seriously sloppy. Once, the issue was a bare, loose 24V wire that had worked its way up into the electronics of the devicenet control module for one of the drives and welded itself to the CB.

First, gather information.

Ventillation?
Is the cabinet dusty?
How are the runs from the drives to the motors? Derating and distance can be an issue.
What is the incoming voltage?
Is this happening in a single area (from a single transformer)
Do you often get drive faults (indicator of a voltage issue)
Have you guys made any changes (capacitor bank or such on utility side)
Age (are these failing drives of about the same age)

Just follow the breadcrumbs.