I've tried to contact Emerson but can't get anyone on the phone. Basically the drive is supposed to detect the phase angle itself after an autotune but the number is waaay off every time. If I enable the drive the motor will just chatter uncontrollably. So I've been putting the angle in manually and listening for noise until I find a number that works. (This number is usually at least 100 degrees different than the auto tune number). This however leads to the problem of the drive tripping with the error ENC10 and needing disconnected/reconnected (resetting will not work) 3 times before it will work. After the 3-4 trips the drive operates as it should for a couple of days use and then will randomly trip again; requiring the disconnect/reconnect procedure. It happens on all 3 drives and motors so it's got to be something we're doing wrong.. unless this could be an effect of the quality of power coming into our building??? Anybody else ever have this problem?

 

Matt,

Not sure of what motor your are using, but I have to assume it is one of the Emerson/CT Servo motors with Hall Sensors.

It sounds like it is not phasing properly, which since it happens on many drives and motors, I would assume that the halls in the servo are not connected properly i.e. wrong hall orientation to the motor phase orientation.

I have experienced what you have on other brands of motors and drives, I used an o-scope to determine what was wired wrong. An easy fix�would be to rotate all three phases until it works. (NOTE: not swap two phases but rotate all three). i.e.:

Original (Motor/Drive) leads
U->U
V->V
W->W

Rotate (Motor/Drive) leads Once:
U->W
V->U
W->V

Rotate (Motor/Drive) leads Again:
U->V
V->W
W->U

If it still doesn't work after this then?

I have had very good luck with the Classic Unidrives, and have used a few Unidrive SPs with very good success. And their tech support has always been helpful for me.

Did you try their Minn # 952-995-8000, and I don't know if they still do support out of Grand Island NY, but they were always helpful too (if you can find that phone #). If you can't get them, then you can try my local support # for my distributor. They have always been the best phone support. 317-844-7328.

Are you doing control via the actual Unidrive speed/position loops, or are you doing it via torque control and an external position/speed controller??

Hope this helps.

BW

 

I apologize for the first reply, that would not fix your problem, I mis-understood what you stated. I will say this much, I have seen what you have happening with some of the Classic Unidrives, and what I had to do was fudge around with some of the tuning parameters etc. before the autotune, to get an acceptable/stable autotune. Again, just call my local support and they should be able to help, if you can't get a decent answer from CT.

 

Are you certain that the motor is completely unloaded when conducting the phase test?

Also, you don't state whether you are using resolver feedback or hall (U,V,W) encoder tracks.

It is imperative that you have the correct current rating associated with the motor nameplate programmed into the drive and appropriate current limits set as well.

I have found that poor commutation offset calculations are most frequently associated with 1 or more of the following causes.

1.) Motor loaded when trying to determine phase offset.

2.) Severe noise on the quadrature encoder signals resulting in the drive losing track of the rotor position and commutation phase angle accuracy decaying over time (requires a power cycle on the drive to initiate re-alignment)

3.) Current limit set too low in the drive such that it cannot develop enough torque to control open loop rotor position and gain an accurate phase offset reading.

We have applied several hundred SP drives in servo rotary and linear motor applications and I have generally been pretty happy with the phase offset feature and reliability of results.

 

Hi

I have come across the exact same problem, i fitted a control techniques unidrive and unimotor and it operates perfectly. I have gone ahead and fitted another two exactly the same system but am having random enc10 trips on the unidrive(encoder phasing angle incorrect). did you manage to solve your problem, can anyone offer a solution??

Thanks
Brett

 

Hi
i have faced the same problem but i managed it by applying to processes

1- put the rated current correctly
2- put the phase angle manually if it is not known then put different value and try to auto tune it in running mode.

it helped me to reduce enc 10 trip in uni drive sp