Felder F700z VFD

[Bob Andre]

My 700z shaper died a month ago. Spindle coasted to a stop and will not restart. Lenze Vector 8200 inhibited. I have been on the phone with Felder tech and we felt the vfd was kaput after diagnostics. Ordered a new one from Austria-still no function. Now we think the new one is not functional as we can't find any other reason for the inhibit. Has anyone else experienced this? We are at a point of possibly installing an aftermarket vfd for single phase to 3 phase as the 8200 model is discontinued and very expensive. No complaints with Felder tech-we just can't get it running. Any help appreciated.

[Joe Jensen]

I am sure you've exhausted all the safety switches and the VFD looks like it powers up? Lenze website shows the 8400 series as the replacement for 8200. I also assume the programming is basic and that Felder would be able to tell you what parameters to program. Do they seem willing to do that?

[Malcolm McLeod]

My 700z shaper died a month ago. Spindle coasted to a stop and will not restart. Lenze Vector 8200 inhibited. I have been on the phone with Felder tech and we felt the vfd was kaput after diagnostics. Ordered a new one from Austria-still no function. Now we think the new one is not functional as we can't find any other reason for the inhibit. Has anyone else experienced this? We are at a point of possibly installing an aftermarket vfd for single phase to 3 phase as the 8200 model is discontinued and very expensive. No complaints with Felder tech-we just can't get it running. Any help appreciated.

I think I've worked on 1 Lenze, but it was years ago - - so take this for what it's worth...

Nearly all VFDs have some type of 'inhibit' function to allow it to integrate with other components in a machine (or system). I would expect to use a drive's parameters to setup the inhibit function to look for either a physical input or a specific communication register. I would also expect to find that there is another parameter telling the function whether the data source should be hi/on/true/1 when inhibited, or lo/off/false/0 when inhibited.

In your case, I'd guess that the 'inhibit' data source would be a physical discrete input, series wired to pass thru overloads (if so equipped :: doubtful), any e-stops, and any limit switches (on guards, covers, lift-up tables, etc..). If true, you should be able to measure voltage at the input terminal. I hope you have electrical schematics and you can work thru this.

If there is no electrical problem found, I'd look at how the function is set-up in the drive parameters.

[Rod Sheridan]

Hi, as others have said, is the new VFD programmed properly?

Are all safety switches working?

Emergency stop button not closed?

Regards, Rod.

[Bob Andre]

Thanks for the responses guys. This whole thing was initiated by turning down the variable speed control while running. We checked it out and it is functioning properly as it varies voltage to the input on the inverter. The new 8200 came programmed by Felder. We also received the parameter list and verified on the inverter. Also verified that all safety switches were functioning and that the correct voltage was applied to the inverter to enable. Line voltage and wiring is also correct. Perplexing. We are currently looking into which inverter Felder supplies currently as the 8200 is discontinued and I don't believe the 8400 meets our application. A source in the US for these is Brandfield, which is much less expensive than Felder. The inverter shipped from Austria was poorly packaged and bounced around inside it's box. I was surprised that it was packaged so poorly for such an expensive and heavy instrument. Frustrating with what has been a fine piece of equipment.

[Malcolm McLeod]

Can’t fathom how adjustment while running / under load could be root-cause?? I spent all morning doing just that on 3 VFDs with 150 hp pumps, running near full load (tuning speed control loop). It’s done in literally millions of applications every day.

...maybe just coincidence?

I don’t have ready access to user manual, but maybe find a way to disable the inhibit function as test. Reaching, but sometimes the displayed fault is masking another underlying problem.

[Bob Andre]

That's what I thought too Malcolm. We've tried to disable inhibit to no avail. It must be coincidental as I've adjusted this many times and the variable speed circuit checks out ok. Still wonder if there is some unknown inhibit or the second vfd was a dud. If it was inhibited I don't believe we would have enable voltage at the inverter. Felder has been pretty patient and helpful, but it has been a month now with no workee.

[Joe Jensen]

My KF700SP has variable speed and a Lenze VFD. I adjust the shaper speed all the time with it running. Never thought not to. I think that you were adjusting when it stopped is a cooincidence. I know that TECO will diagnose and test their VFDs for you. Perhaps see if Lenze will do that for your original one?

[Chris Parks]

Just find an industrial electrician, he will diagnose it while others just guess and most probably save money in components that are not faulty.

[Rod Sheridan]

Just find an industrial electrician, he will diagnose it while others just guess and most probably save money in components that are not faulty.

Or even better find an electrical Tech.............Rod.

[Bob Andre]

Success! It turns out that Lenze made a revision to the inverter and the new one was one with the revision that was not documented with the inverter packaging, but buried in a 548 page manual. There was an extra input that required 20-30v dc to enable the inverter. Tested it out with a Dewalt battery and all is fine. I've ordered a 24v power supply that I can retrofit and we are good to go. An expensive and lengthy process. Still don't know why my original inverter fried. The old inverter made in Germany, new one in France. Thanks for all your spot on advice everyone.

Bob

[Joe Jensen]

Fantastic news...joe

[Malcolm McLeod]

Fantastic news...joe

^Seconded^

Take a careful look at the terminal strip on the drive. It probably has a 24VDC source on it. If so, you should be able to jumper this voltage 'source' to the inhibit terminal..?? Or, pass the wire thru a E-stop switch, etc.. Lenze is not your average Chiknockoff VFD, so I'd be surprised if it is not so equipped.

[Bob Andre]

The dc voltage available from the Lenze is 20v and the circuit calls for 20-30v. It's very easy for me to draw 120v onto a 24v dc supply so that's the way I'm going. I should have the part from Amazon tomorrow and I can retire the Dewalt battery! A thank you to the Felder tech that worked with me is in order.