1336 plus 100 hp drive problem

I have 3 100 hp drives wired as follows; 250@ circuit breaker, line reactor, and 200@ fuse trap then drive. Recently I have ran into a problem that after the drives sit deenergize for a day or 2 and are powered up, one of the drives trips out the circuit breaker and no fault other than loss of power is in the que. It again happened the other day.
After reseting the breaker and bringing the drive up, I ran the drive sporatically throughout the day with no problems.
Call to the factory was a waste of time! Could the precharge circuit be on the way out? Is there any diagnostics I can do? The motor and reactor meg fine. All three drives showed the same impedance readings. The only thing I saw different was that the faulty drive had an output voltage of 10 vac versus the other 2 having ~1vac leak.

Check the breaker INSTANEOUS trip setting. You might try and turn it up a bit. The cap bank is totally discharged and the in-rush can "appear" quite high. I have seen breakers that see that initial RATE of current rise (di/dt) as a problem and trip even though the actual current draw is not over the actual CONTINUOUS trip setting.

Pre-charge resistors are either good or open. You can test the actual value by measuring across the pre-charge contactor when the drives are powered off. You might make sure the pre-charge contactor is fully opening up while you are at it. I have seen a few that arc'd partially shut. You should be able to manually close it and let it open to test.

Hope this helps a bit.

Your precharge circuit could definitely be acting up although the instant trip setting the CB is more likely.

The problem to look for in the precharge circuit is the resistor bypass relay contact arced closed. When that happens, there is no precharge action and larger-than-normal inrush currents occur. Bus capacitor failure would be the next thing if the problem isn't corrected.

I have 2 1336 drives here and had a problem where when over a weekend of being down the power for one of the drives was turned on and the drive blew up...After a week of waiting for a refurbished drive "cause they dont make these anymore" I installed the "new one". After a couple of weeks I had the same problem. So I talked my boss into letting me order a powerflex700 drive and a line reactor. 7 or 8 months later I am having no problem. I am just waiting on the remaining 1336 to blow up so I can replace it with a drive that AB still makes..


DUNK

BTW

This problem all started with breakers tripping out. So you may want to concider a different drive.


DUNK

DUNK, you wouldn't be the Allen-Bradley drive salesman in JoeSullivan's territory now, would you?

These are, after all, 100hp 460V drives----chump change to some but serious money to most!

NO man....I work for pioneer foods.
We just so happen to have a lil money set back when this problem came upon us.

DUNK said:

I have 2 1336 drives here and had a problem where when over a weekend of being down the power for one of the drives was turned on and the drive blew up...After a week of waiting for a refurbished drive "cause they dont make these anymore" I installed the "new one". After a couple of weeks I had the same problem. So I talked my boss into letting me order a powerflex700 drive and a line reactor. 7 or 8 months later I am having no problem. I am just waiting on the remaining 1336 to blow up so I can replace it with a drive that AB still makes..


DUNK

Click to expand...

Had the same problem a couple of years ago with a 1336..Installed line reactors..Still have 10 or so in the plant...Those things are kick *** Tanks!! take a beating and still run.. The newer ones have some nice fancy features on them but they just dont "feel" as robust as a 1336..

Just my 2c

Just my humble opinion, but the 1336 was NOT a tank, far from it.

For those who don't know, the 1336 in that size didn't have a precharge resistor circuit. A-B got cheap and stuck in an SCR front-end instead of diodes, then they ramped the voltage into the caps to try and avoid the inrush. It was spotty at best and tended to fail a lot. I remember the first time a customer called and told me "The SCRs blew on the 1336 drive" and I responded "There are no SCRs on it, don't you mean the Transistors or the Diodes?" I got a rude awakening and as it turned out later I was to spend a significant portion of my life fixing those pieces of junk! I stopped buying A-B drives as a result. I can't speak for the Powerflex other than performance-wise I have had installations where I put other brands next to them and users are always happier with the other brands.

joesullivan8,
Most likely you have a failure of the ramp board on that SCR front end and it is gating immediately instead of ramping, or one or more of your SCRs are shorted. If it works sometimes and not others, then I would suspect moisture is condensing on the ramp board when you are powered off over the weekend. If this is happening every time you power up the drives, you need to replace that board and/or the SCRs before you kill something else down stream.

i cannot comment on that size of drive..the biggest 1336 drive i have delt with was 30 hp at 600v..

I must admit i only know the basics of how the drive works..As a sparky we are not trained to deal with board level problems..it works or it dosnt..if we have time i might be tempted to pull one apart and see what makes it tick but for our customers it is usualy cheaper to junk the drive and replace if it dosnt work..

two things i have learnt...dont buy an AC tech drive (Or Lenze or about 50 or so other brands that they are mass produced on) and dont by an ABB (Thats just sour grapes for me becouse i had a bad time with one of they sales reps!)

As for AC tech..i just havent had any luck with them..but i have heard (And i dont know if it true or not) that they are rated at 575v. We in this plant are running at 600v during the day and drifting up to about 620 or so at night..

But all of the above is WAY O.T!!
Back to the problem at hand.. Most people dont know about the settings or different styles of beakers.. If you have a 250 amp breaker chances are it has dial settings on the front..These should not just be set at a whim.. These interact with short circuit interupting capacity..If it were me i would spend the $ to get a co-ordination study done..This will tell you exactly where those settings should be..

Again just my 2c

I kind of agree with DarrenJ, I've worked around literally dozens of them for years and NEVER had trouble with any of them. I too was disapointed when I saw the new Pflex, it looked like a toy compared to the 1336.


Having said that the only trouble I have had with the 10 or so pflex drives that I have installed was self induced (got an expensive lesson on drives hooked to a resistive ground transformer).

If you have two identical drives and cb's, try swapping the cb's that way you will know if the problem is your drive or your CB. Don't spend too much time chasing the motor as that is not likely your problem.

Tell you what, I do not know jack c*ap about the 1336 in general, worked with it very little. I also thought it was a POS.

I would bet my last dollar though that jraef does know and speaks from experience.

I too can not and would not dispute jraef, it sounds like he knows what he is talking about. I have never been a drive repair technician. I just replace them when the smoke gets let out. I was surprised by his comments based on my previous positive experience with the 1336.

One of the plants I worked at had about 40 SEW eurodrive movitracs. I was convinced that these were the biggest POS on the planet. We replaced one of these every two weeks. We looked like a pit crew, when one blew the electrician on shift grabbed another one from the store room and I headed down with the laptop to program it. We could change a 40HP drive in 15 minutes.

Anyway, the next plant I went too also had about 10 of these same drives. When I got there I inquired about reliability. They had been in service for about 8 years and had 0 problems, they didn't have any spares or even the programming software. So I don't know if the problem was the drive or the installation. I had checked everything I could think of with the installation and followed all of SEW's recommendations with no luck.

I recently had a conversation with an ex technician from a major U.S drive manufacturer. I told him how I thought their product had gone downhill in recent years. His response was that drives manufactured in country X and Y were still very good, and the drives manufactured in Z were ****. It's tough to tell where something is made from a catalog so I will make sure I never buy anything from that company again.

my $.02

Being a drive repair tech, I have seen my share of just about everything. The 1336 is like some folks say, the ford/chevrolet of drives. Some times they work great, some applications they are not suited for. I know of one plant full of 1336 drives that had nothing but problems and it was a minor programming change to fix. AB recommended they replace some rather expensive gear boxes.

Some on poormouthed ABB based on a sales rep. Please do not punish the drive for the sins of the sales slut. IMO ABB are one of the better ones out there.

I have seen too many drives that are being run at their max capacity and they usually are problamatic. Then you find a few drives that the customer has absolutly NO problem with them. Then you find out they only load them to 60-70% max with 50% load typically.

These days there are SSSSSSOOOOOOOOO many drive mfgrs competing for business they do not build in any robustness. Once upon a time you could load a drive 15 to 20% overload and not bother the diodes/scrs/transistors as they were actually 50% bigger than needed for the HP range.

Today a drive is rated at 36 amps and the scr's are rated 36 amps. The quality of parts is such that under IDEAL conditions there is no problems.

IDEAL being the word. Has anyone found the IDEAL condition yet???? I sure have not.

I have seen ssssoooo many drives like the 575 volt one mentioned that has to endure 600-620 volts. Usually around here they are 460 volt drives having to deal with 505 to 520 volts. Most maintenance people freak out when I tell them their drives are rated 460 volt +10% -5%, NOT 480. So I just show them the mfgr's labels or spec in the manual when they actually have a manual.

Rant over.

For most applications anymore I've seen more and more plant specs request to size VFD's one size higher than than the motor rating. (e.g. 10hp motor requires a 15hp rated drive)