# Powerflex 700 Question of the Day



## glen1971 (Oct 10, 2012)

I'm wondering if there would be (or could be) any damage done to a drive if the incoming power was taken to the T1/T2/T3 terminals instead of the L1/L2/L3 terminals?

Had one that was swapped on the weekend and they couldn't get it to run. It had power to the HMI but would give an OC Fault when they tried to start it..

It was wired:
L1 went to T1
L2 went to T2
T3 went to T3
T1 went to L1
T2 went to L2

I shut it down, swapped the wires and reenergized it.. Checked the parameters which were all good, started it, checked rotation and it's been running fine all day..


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## Cow (Jan 16, 2008)

A few years ago, one of coworkers wired an AC Tech to the load side, it let the smoke out instantly. I assume all drives would have the same fate. That was a cheap drive, I sure wouldn't want to make that mistake on a PF700.:no:


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## glen1971 (Oct 10, 2012)

Maybe it's only saving grace was it is on a single phase service? I'm gonna check it again this morning and see if it survived the night....

Funny part of money wasting though... When they swapped the drive out, they got it from an adjacent spare that was never energized.. It was installed 2 years ago on a pump that had all of it's piping ripped out 4 years before that... At least they got to use the "spare" before it was demolished.. lol...


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## Guntrician (Jun 20, 2012)

I'm happy to say I don't know if it would damage it. Being most 700 frame sizes have the Line and T terminals in very close proximity of one another, it would be easy for someone inexperienced to mix that up if not paying attention. So it wouldn't surprise me if AB has some protection built in for this. Honestly don't know though. The fact that yours is running is encouraging. Now if you asked if hooking up 120v control to a 24v control module would damage it, I can give you a definite "yes". Instantly.


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## mikey383 (May 21, 2012)

I'm curious to know the answer also. I know it's a big no-no to do a megger test on the load side wiring while still attached to the drive, but not sure about hooking line voltage to the load side.


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## JRaef (Mar 23, 2009)

You cannot make this generalization about all drives, and not even all AB drives. But the "7" class drives (70, 700, 750 etc) do have ONE level of protection in them, giving you essentially ONE SHOT at doing it wrong. the drive will detect the problem and immediately turn off the transistors so that they will not be damaged and give you a fault. If you PERSIST long enough and keep resetting the faults, as LOTS of people do, it will EVENTUALLY get you to a point where you are then permitted to pop the transistors, and once that happens, everything cascades into a complete "magic smoke" event, leaving no circuit unaffected.

Bottom line you were lucky on two fronts: it was an AB "Architecture Class" (7 series) drive, because they are one of the few who take that extra step, and your guys did not persist on trying to force the round peg into the square hole by smashing it with a sledge hammer.

If it works at all, you should be fine. the transistors MIGHT be stressed a little, meaning the damage may have taken a few years off their life, but if you are not abusing them, you may never notice.

Just for future reference, the 4 and 5 series "Component Class" drives are like everyone else, they would have popped immediately and the entire drive would be toast. I had someone do that to me on a 250HP ABB drive, it was all over in less than a second. He was an HVAC technician who claimed he was 'qualified" to wire up a 250HP drive. When I came to intervene it was too late of course, but I got to talk to the guy. is claim was that the instructions were not clear enough. Here's how he put it:

_"The breaker feeding it has terminals that say "Load", and the motor has terminals that say "Line". So I connected the drive "Line" terminals to the motor "Line" terminals and the drive "Load" terminals to the breaker "Load" terminals. What's the problem?"_


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## tates1882 (Sep 3, 2010)

Guntrician said:


> I'm happy to say I don't know if it would damage it. Being most 700 frame sizes have the Line and T terminals in very close proximity of one another, it would be easy for someone inexperienced to mix that up if not paying attention. So it wouldn't surprise me if AB has some protection built in for this. Honestly don't know though. The fact that yours is running is encouraging. Now if you asked if hooking up 120v control to a 24v control module would damage it, I can give you a definite "yes". Instantly.


 I have that shirt also. At least the 700 series the control cassette can be replaced easily, on the 70 series not so much. And on that same not reversing the polarity to a 24vdc safety relay will also make nice pretty smoke. Plc guys and switching the freaking negative through the io


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## Safari (Jul 9, 2013)

Going for the 7 series ABB .......


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## RIVETER (Sep 26, 2009)

glen1971 said:


> I'm wondering if there would be (or could be) any damage done to a drive if the incoming power was taken to the T1/T2/T3 terminals instead of the L1/L2/L3 terminals?
> 
> Had one that was swapped on the weekend and they couldn't get it to run. It had power to the HMI but would give an OC Fault when they tried to start it..
> 
> ...


Lest we forget that a motor winding is no more than a transformer anyway, what harm would it be?


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## Guntrician (Jun 20, 2012)

tates1882 said:


> I have that shirt also. At least the 700 series the control cassette can be replaced easily, on the 70 series not so much. And on that same not reversing the polarity to a 24vdc safety relay will also make nice pretty smoke. Plc guys and switching the freaking negative through the io


Roger that. That is a nice feature. The damaged and quite smelly cassette comes in handy to stick under the PLC programmers car seat. Took him a day or two to figure out where that burnt electrical smell was coming from. Lol!


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## Guntrician (Jun 20, 2012)

By coincidence we had a Rockwell fella tag along with the CED sales rep on the 21st. They fed us some lunch and brought in one of their Pelican Case enclosed portable 753 training stations to let a couple of the newer guys practice navigating the files and what not. I asked the Rockwell guy what would happen in the OPs scenario. He claimed it would let the smoke out. 

The elect. dept. supervisor heard me ask this question and chimed in that he witnessed a backwards wired 700 go up in smoke and said it was a bit loud when it did. I told the story posted here. The Rockwell guy was surprised the OPs drive "ran" after the mis-wire. I know the electrician that wired the drive that the elect. supervisor witnessed burn up. I'd bet money if it didn't fry it on the first attempt and it faulted, he likely tried starting it a second time.

I'm going to just keep wiring L to L and T to T and not press my luck. Lol!


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## triden (Jun 13, 2012)

I can tell you from experience that a cheap drive (read: automation direct) will instantly blow up if you fed line to the output terminals. Paying money for a drive pays off in the end.


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## glen1971 (Oct 10, 2012)

Guntrician said:


> By coincidence we had a Rockwell fella tag along with the CED sales rep on the 21st. They fed us some lunch and brought in one of their Pelican Case enclosed portable 753 training stations to let a couple of the newer guys practice navigating the files and what not. I asked the Rockwell guy what would happen in the OPs scenario. He claimed it would let the smoke out.
> 
> The elect. dept. supervisor heard me ask this question and chimed in that he witnessed a backwards wired 700 go up in smoke and said it was a bit loud when it did. I told the story posted here. The Rockwell guy was surprised the OPs drive "ran" after the mis-wire. I know the electrician that wired the drive that the elect. supervisor witnessed burn up. I'd bet money if it didn't fry it on the first attempt and it faulted, he likely tried starting it a second time.
> 
> I'm going to just keep wiring L to L and T to T and not press my luck. Lol!


Thanks for asking your Rockwell rep..
I'm thinking that the only thing that saved this drive was it was being supplied by a single phase service... Definitely not something I've seen before or would even think of trying! But it's been running smooth since...


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