I am looking for the formulas or concept of calculating or estimating the new overload settings once power factor correction capacitors are installed at the motor terminals. Remember the capacitors are downstream of the overloads therefore there is a decrease in current seen by the overload...
I came across late 50's low voltage MCCs and noticed all of the MCCs have reactors(current limiting) in series (between the incoming from the transformer to the line side of MCC) or MCC feeding another MCC. There are no nameplate or information available what so ever. Is there a way i can...
Yes on Delta-Wye,one can see the voltage through multilin 469 MPR relay and it stays 2400V. This particular motor is the only load on the transformer. The Delta-Delta transformer is also 2400V. Once a year voltages are measured at the secondary of the transformers. One thing i found out is one...
Thanks for all the thoughts, the currents were measured directly at the cables through flex CT's. This eliminates the CT error or location issue. My initial thoughts were about transformer tap differences, but calculations didnt compensate for the approximate 40A difference. Since amps were...
Thanks alot, I am trying to get the original rewound reports (15 years old issue). There seems to be only three leads at the packerd head coming out from the motor casing. Quite possible one of them is wound wrong. What bugs me is the fact I was told that motors are switched around in the past...
I have an interesting question if any one can help.
2 identical compressor motors with the following data.
600HP, 2300V, 390RPM, 152FLA
Both were run uncoupled to check the amps.
One being fed from Delta-Wye transformer with the following data
12470V-2400Y/1383
2000/2240(OA) KVA, %Imp 5.24...
