# ABB Drive issue



## Surge03 (Sep 23, 2012)

surge03 said:


> i haven't really worked on vfds much but running into an issue on one of our drives. It's. Abb ach401601132, in drive it goes into fault 1 and fault 27 but works fine in bypass mode, i have cleaned it made sure the fan is working. Voltage and current is good on bypass mode. This is for two 3 hrp motors at 480v 3 phase for s cooling tower.


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## Chris1971 (Dec 27, 2010)

Surge03 said:


> View attachment 61530


I found the users manual for the drive model # you posted:



https://library.e.abb.com/public/cb...04422cc/3AUA489002B5311_ACH400_00_UM_REVE.pdf


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## Jlarson (Jun 28, 2009)

F27 points to a drive hardware fault. Contact your ABB rep, probably new drive time


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## varmit (Apr 19, 2009)

Fault 27 would normally indicate that the VFD has failed and needs to be replaced.


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## Chris1971 (Dec 27, 2010)

Jlarson said:


> F27 points to a drive hardware fault. Contact your ABB rep, probably new drive time


Looks like this drive is around 15 years old.


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## JRaef (Mar 23, 2009)

They haven't sold the ACH400 line for well over 10 years, it's likey you will find it is no longer supported.


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## Jlarson (Jun 28, 2009)

Yeah it's time for a 550.


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## varmit (Apr 19, 2009)

That is an impressive life span for a VFD to be in use. Most don't survive nearly that long.


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## Safari (Jul 9, 2013)

varmit said:


> That is an impressive life span for a VFD to be in use. Most don't survive nearly that long.


Really? Please provide more info.guess its time for me to start getting back-up for all the drives.

Sent from my HUAWEI Y330-U01 using Tapatalk


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## Surge03 (Sep 23, 2012)

varmit said:


> That is an impressive life span for a VFD to be in use. Most don't survive nearly that long.


Ya it was really dirty, so I took it apart and cleaned the heck out of it but still nothing. Any tips on how to troubleshoot a vfd? When I was in school I learned that voltage stays the same but frequency controls the speed, is this correct? I was getting 150 volt A,Bphase 250voltB,C at 58 hertz when input voltage is 3 phase 480 I don't understand


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## micromind (Aug 11, 2007)

VFDs are pretty complicated electronic devices. I seriously doubt if it's repairable even if you had the diagrams and test point specs. Often, a drive manufacturer will spec a certain chip and buy a run of them. Once the run is done (usually because the drive has been updated), they are no longer available.


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## misplaced1 (Aug 5, 2015)

Surge03 said:


> Ya it was really dirty, so I took it apart and cleaned the heck out of it but still nothing. Any tips on how to troubleshoot a vfd? When I was in school I learned that voltage stays the same but frequency controls the speed, is this correct? I was getting 150 volt A,Bphase 250voltB,C at 58 hertz when input voltage is 3 phase 480 I don't understand


Fault 27 is saying faulty drive anyway. Dirty or not. As to your other question....the voltage readings are not the same as the drive is actually putting out a pulsated DC voltage. Trying to read that with a DMM set to AC volts will never give you a true reading. 

When are in bypass.....the drive is actually doing that.....bypassing the VFD electronics and sending the full 480 straight to the motor.

Its time for a new drive. Look into the ACH550 line. Excellent drives.


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## JRaef (Mar 23, 2009)

Surge03 said:


> Ya it was really dirty, so I took it apart and cleaned the heck out of it but still nothing. Any tips on how to troubleshoot a vfd? When I was in school I learned that voltage stays the same but frequency controls the speed, is this correct? I was getting 150 volt A,Bphase 250voltB,C at 58 hertz when input voltage is 3 phase 480 I don't understand


Although it's true that voltage measurements of the output of a VFD with a basic VOM are pretty much useless, the high level of disparity here indicates that it's likely that one of your transistors has failed. You could replace them all I suppose (replacing only one leads to the others failing soon after anyway). At that age however, they are likely obsolete so even if you found them somewhere, they will be very expensive and maybe even as much as a new drive by the time you are done, with no absolute guarantee that this is the only problem.


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## misplaced1 (Aug 5, 2015)

JRaef said:


> Although it's true that voltage measurements of the output of a VFD with a basic VOM are pretty much useless, *the high level of disparity here indicates that it's likely that one of your transistors* *has failed*. You could replace them all I suppose (replacing only one leads to the others failing soon after anyway). At that age however, they are likely obsolete so even if you found them somewhere, they will be very expensive and maybe even as much as a new drive by the time you are done, with no absolute guarantee that this is the only problem.


Great advice JRaef. I've been working with ABB drives for a long time in the HVAC controls industry and can say for certain that you're right in saying the AC400 is obsolete and parts are incredibly hard to find. 

Not really worth putting any money into it especially since a new replacement ACH550 drive would be in the 800 dollar range.


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## oliquir (Jan 13, 2011)

anyway a 15 year old vfd should also have their capacitors changed, but do you really need an abb vfd, there are half price models that do the same job as the old 400 one


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