I have been experiencing some ski-sloping problems with a couple of our Enpac 1200A data collectors. I did some comparison testing today using 4 data collectors. Measurements were taken from a stud-mounted accelerometer using the same cable and collection parameters. The attached file shows some waterfall plots comparing the spectral data from each data collector utilizing different number of averages. The data indicates that 2 of the data collectors (M3-6648 and M3-6649) exhibit ski-sloping whenever 2 or more averages are used. Have you experienced this with your Enpac 1200A data collectors?

FYI – I have been pursuing this with the vendor (Entek/Rockwell).

Ski-Slope.doc (284 Kb, 42 downloads)

Bueller? Bueller? Anyone?

Either no one cares (probably) or this post got buried under the avalanche of recent posts. So, I'm bumping it to the top to see if I can get a response from the Enpac users out there.

Steve

Steve,

"either no one cares ...."
Or no one is using a 1200 any more
I don't know, but I have a 2500 and don't seem to have the problem you are showing there. I remember the problem when I was installing a new version of Odyssey in Arkansas at a paper mill, but I don't remember what they were told about it (CRS Disease).
Anyway, just wanted you to know someone did care , just don't have an answer for you.

Dave

Steve, I just want you to know that I care too... (OK, group hug, EVERYBODY!) ...and not just because it's Valentine's Day!

Anyway, for what it's worth, we have a 1200 as well as a 1500. We are also testing a 2500. I don't recall seeing this low-end ski slope in velocity, however we did experience this periodically in g's, somewhat intermittently. It may very well have been data collected using the 1200, but there is no way to tell. I can tell you that we changed to a 318 cpm filter to eliminate this problem, but that obviously won't help you here, however.

So, I guess the main thing here is that "I care"... (lol)

Thanks for the responses!

I wouldn't mind getting the 2500, the color screens are very nice. It just perturbs me that we would be rewarding Rockwell (new PO) for not fixing diagnosing and fixing their equipment.

Thanks again for caring

quote:

Originally posted by Steve Ciesla:
Thanks for the responses!

It just perturbs me that we would be rewarding Rockwell (new PO) for not fixing diagnosing and fixing their equipment.

It's not any different with the 2500. It still has some problems that they have supposedly been working on for over 2 years now.

Good luck getting anyone from Rockwell interested.

Dave

quote:

It's not any different with the 2500.

Dave, have you seen this ski slope as well? Have you associated it with the number of averages?

Andrew,

That quote you quoted has nothing at all to do with the ski slope. read the posts again.

No, I DO NOT have that particular problem with the 2500.

Dave