@jreaf: Initially, yes, a Static auto-tune was performed. However, the drive has be reset to factory defaults in preparation for this weekends trial setup per AB Tech Support recommendations.
b]@jreaf:[/b] One of the AB tech support persons made that statement, I was very clear in my question, "Will the PowerFLEX 753 VFD operate a delta connected motor?", long answer was no. I agree with you and questioned it, and again, was not given a clear answer. I contacted AB support again...
@LionelHutz: At ~18Hz, we are drawing less then 1 inch WG on inlet side of duct. It seems to me that there is hardly any load at all.
I agree that the VFD should work fine on a delta connected motor. Can you elaborate on motor and VFD/Hz pattern needing to match?
Again I agree, the fan...
@waross: The difference in fans are as follows:
EXISTING FANS:
~36 inch diameter, ~24 inch width, belt driven, running ~1800+ RPM
NEW FAN:
~72 inche diameter, ~19 inch width, direct coupled, 1160 RPM
I wish I had good news to report...
@iop95: We input your parameter recommendations which yielded marginal results. Was unable to get past 18Hz before reaching FLC.
@jreaf: Motor uncoupled from load will run up to base speed (1160RPM) connected delta, current draw ~53 amps (2nd hand...
I have some time scheduled this weekend to visit the site and attempt to resolve this problem.
@waross: I will monitor the phase currents and advise. I have asked multiple times for the fan manufacture name and model; no response. I will try and locate this information myself this weekend. The...
@waross: Bro, I would NEVER consider someones advice as a waste of time while trying to resolve a problem [bigears]. Regardless of the motors condition (new vs rewound), I have all ready suggested that it be uncoupled and ran. That was done, results; motor ran up to base speed, current about 25%...
Thanks all for responding, all good advice.
Answers / clarifications to your responses:
@jraef: Connection diagram is correct. Yes, motor was not only checked but replaced (had new spare on hand). Distance between drive and motor = ~250', line and load reactors installed within 6' of the...
NEC 230.95 Exception 2: The Ground fault protection provisions of this section SHALL NOT APPLY TO FIRE PUMPS
The use of the word 'SHALL' in NEC is mandatory
Note that NEC articles regarding services pertaining stand-by/back-up generators should be reviewed and discussed with the AHJ and/or...
Curious, what loads are on the system that would require 240V Delta? Does a grounded system pose a higher risk to personnel safety or the facility? If it {the 240 delta] was installed over 75 years ago, what remains that has not been replaced over the many years? Being able to answering this may...
"MAIN QUESTION: Are plant personnel (with motor experience but no special UL certification) permitted to disassemble the motor to replace bearings?"
1) In a nutshell, if it has a UL rating, it must be serviced by a UL registered shop to keep that UL rating. (they actually re-certify the...
