Recent content by Grubbs1960

Baluncore said: Does the current fall, under no load, as you increase the running frequency from 50 Hz to 100 Hz ? Yes. At 50 Hz, the amperage is 2.4A, and remains at 2.4A at 60 Hz. It drops to 1.8A at 75 Hz and to 1.3A at 100Hz.

Done, see my reply above to Baluncore. During discussion with the VFD tech, he suggested the same thing, so it was in that mode when I was reporting the results in my post #58. I have had set the ramp up time to 5 seconds for all of the tests previously discussed.

If I understand this correctly, you are suggesting that I can reduce the amp draw at the lower frequencies by lowering the output voltage from the VFD. I will give this a go. If I lower the voltage, do I need to keep the frequency above 60 Hz or does the lower voltage allow even lower frequency...

One thing that I did notice is that the voltage on the tag reads 220v. I had been thinking it was 230v, which is what I set that parameter to. I haven’t changed that. Maybe I should? If I wire it to the 600 rpm configuration, yes, it starts pulling higher amperage above about 24 Hz, even with...

Not sure what happened there. Hopefully it will work this time. Yes, new drive, configured for US and 60Hz It is in general mode. I currently have P-08 set at 3.0 amps. I haven’t seen it pull more than 2.5 except when ramping up. The speeds listed on the plate are 600-1200-1800-3600...

I hope it’s perfectly normal. I was able to set up and turn an approximately 2.5” (525mm) diameter red oak cylinder with amp draw never getting greater than 2.5 amps. I’m becoming more confident that there is probably no issue, at least with this set of windings.

After 7 minutes of continuous running at no load, the stator temp rose from 22.9C to 23.6C. At the end of this trial, the copper wire of the windings was 25C. This seems reasonable to me, but I have no other experience doing something like this. I also measured voltage across each of the three...

I perused my manual again and found no input parameter that would allow me to enter the number of poles. Here’s a link to the manual:(https://admin.invertekdrives.com/assets/A09D2FA5-3BCD-4511-BA4D-A4878F2634AE/82-E3I20-IN_V1.05%20E3%20IP20%20User%20Guide%20V1.04%20ENGLISH.pdf) But there are...

I will try running a little longer while monitoring this. Thanks for the wiki link as well.

Grubbs1960 said: Perhaps it is as simple as even when the switchgear is operated, causing momentary break of main motor with VFD, the VFD is able to tolerate that because it still has a load from the idler motor? Thanks for clarifying. My VFD is an Invertek Optima E3. It will display speed...

I have not noticed any wires getting hot, but I have not left it powered on for more than a minute or so. Would there be some other means of testing to answer this question definitively? I don’t understand what is meant by “reactive current “, but perhaps it has to do with your comment below...

Yes to phase and voltage. I am not familiar with AT1 type designation. Yes Thanks for this, although I still don’t have the understanding that I would like. I don’t believe my VFD has a parameter that allows me to enter number of poles. Is that normally a user entered parameter? This would...

I do not have access to a megger. But I would like to understand this better. My perhaps incorrect/incomplete understanding is that a megger induces a high enough voltage to the windings that if there was a small fault in the winding insulation, it could be detected even though a regular...

I have done some additional testing of the motor and observed some things that are puzzling/concerning: 1. When wired in the 600 rpm configuration, the VFD limits the speed to ~300 rpm because the motor is drawing max amperage (2.3amps). This is with no load. 2. When wired in the 1800 rpm...