The "Yellow Company", the one started by John F. Is very active now. I found a temperature calibrator in the mail. Showing an instrument that probably is OK for temperature calibration and tests.
But my confusion reached new heights when I looked at the instrument. The display says 300.0 V AC. Not what you expect to see on a temperature calibrator.
OK, nice to be able to check mains voltage. But showing an AC voltage somewhat obscures the message. Is it the same in other languages? Or is it only in Sweden that confusion reigns?
BTW, I studied the specs for the 438-II. I don't know about that one. Motor frequency is limited to 40 - 70 Hz and carrier frequency is from 2.5 to 20 kHz. So, if I shall go and have a look at a problem - shall I ask the customer if he can guarantee that the motor is running close to nomina speed? And that the VFD doesn't use 1.2 or 1.8 or some other low carrier frequency? I see a lot of sub-2000 Hz carrier frequencies.
Also, it cannot be used in field 1/sqrt(3) applications or other field-weakening applications. Or have I mis-understood something?
catserveng says (11 Oct 17 17:59) "software interface still seemed slow and clunky" That is a severe warning sign. I waited for that improved software in a four-channel scope several years ago. It never appeared. And PC communication was a joke. Be sure to try that out when you test it. Another thing that I had to wait for in vain was increased waveform storage. That unit didn't have more than the older two-channel monochrome scope (15 waveforms). And when I lost half of the waveforms after a distant job, I gave up and sent it back.
Not that they ignored my opinion. I think the problem was that they didn't understand there were so many and so severe problems. I hope that it has improved now. But watch out - and test all things you need in this device.
Gunnar Englund
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.