% current THD can be very misleading. It is percent of the fundamental current. If the fundamental current is 100 amps on a wire rated for 100 amps, 126% THD is bad. If the fundamental current is 1 amp on the same wire, 126% THD is completely negligible.
Generally, current will almost always...
This type of thing happens because the system is at some point constructed for n-2 or n-1 conditions, and then consumption growth causes peak loading which exceeds the limits for n-1 operation (ie, less than n, no operation). The growth is allowed to occur faster than additional necessary...
The only way that is acceptable as a locking mechanism under any code is if the external lock also prevents opening the door to get to the breaker. Check under definition of lockout in any code ...
If you're looking at NEC issues, 240-3(a) specifically requires NOT installing overcurrent protection where an open circuit will create a hazard and I have always seen this rule applied for protection circuits of large generators. The circuit requires short circuit protection only, which is...
For medium/high voltage cables (>600V), you should contact the cable manufacturer for their recommended test voltage, which is usually done for acceptance testing after installation of the cable. This then gives a comparison to the factory testing results to look for damage.
Once installed and...
IEEE Standards are International:
IEEE Guide: Test Procedures for Synchronous Machines Part I-Acceptance and Performance Testing Part II-Test Procedures and Parameter Determination for Dynamic Analysis
IEEE
1995;Softcover;1995;ISBN 1-5593-7710-0; Product No.: SH94401-TBR; IEEE Standard No...
That's correct. But if the drive goes to current limit and holds at 150%, it will trip after 3 seconds if protected according to the ratings given. If the accel time is set long enough to get the load going and not stay in current limit for extended periods, trips will be avoided. That's...
My bet would be overvoltage at non-fundamental frequencies.
Do you have IGBT VFAC drives?http://www.mtecorp.com/solving.html
You might also check:
http://www.groupeschneider.com/en/pdf/ect190.pdf
Power is power. So the power required by the pump is the power supplied by the motor. The power supplied to the motor is the motor output power divided by the efficiency, and that is the power used. But, if the motor is not operated near full load, it will operate at a low power factor (.75 or...
