We do have working alarms on the motor. In fact one day the press slowed down on its own twice. We never got any readings on the motor past 43 c (40 c is suppose to be normal). The first thing we checked was the tach. The tack does not feed back to the motor control though, it feeds to a PLC then the PLC sends the signal to the controller.
When we checked the tach is was working properly. As said in the original posting, the first thing that happened after the new drive is a speed overshoot at start up repeatedly. Then eventually motor overheat error. My maintenance man would heat gun the drive cabinet but once you open the door it is a false reading. He did it sneaky and came up with 54 c on the heat sync (at 129 f that drive definately kicked out some heat).
The whole reason for this new drive was because our old drive was so out of date all you could do is rebuild them. The newer drives were better and less money than the old with a rebuild. One of the things the installer said that I rememeber was that he had installed several of these drive on presses with great success but the presses were all pre-PLC technology. So our press was the first PLC press with this drive.
I've done a few pre and post.
Pre PLC would be Analog drives such as the AB 1336 or whatever the part number was.
Makes no difference to me.
I've used eurotherms, Control Techniques, whatever the customer wanted and was within its budget.
The drive gets an analog signal to ramp up to a point and maintain speed.
Either PLC or a speed pot will do the job.
Since the tach goes to the PLC and fed to the drive I see no issue with signals unless you have had the uncontrolable ramp up before the install.
I used to retro Harris M110, 110Bs, 300s etc.
I've used all kinds of drives and usually ended up using the existing ones as we were doing primarily the controls/PLC upgrades and the things ran forever.
I cannot see how a "bad" motor worked without a hickup with the old drive, then the Eurotherm and now it is acting up.
I'm out of options here.
No alarms, cooling is more than enough (according to you),no changes were made recently besides the new drives(right??), the only things left are analog signals somehow get scrambled and screw up the drive or the drive itself is bad or misconfigured.
Bringing someone in with a megger wouldn't hurt at this point.
A couple of drive experts on here , you may get something that I've missed so far from them if they decide to jump in DickDV & Leifmotif (sorry about any wrong spelling, not intentional).
