To all of community member,
I really apprecaite your adivces/tips and I didn't expect such large group attention to my post. Anyway so sorry for late update but we couldn't run the motor due to some other process issues.
For a bit more information, this is the lube oil pump and direct coupled...
Really apprecaite your feedbacks.
For more information, we did this motor run coupled with pump. So, it wasn't no load condition, and the supply voltage and freqency were good at approx. 480V and 60Hz. I was told that tachometer was good condition and used for other mootors as well. I...
Hello,
As a part of startup process, we did motor run but the speed is quite lower than the rated speed. Please refer to the following information.
Rating: 1.5HP, 3PH, 460V, 2.1A, 60Hz, 1760 RPM, SF=1.15
But motor running at 1558 rpm and 1.5Amp. So, I don't think it is overloaded at all. But...
Hello,
I will do commissioning tests for a plant synchronization system to control a group of turbine generators (2 ~ 3 generators together) to be synchronized onto the grid. FYI, GE CTG rating: 40 MW & Siemens STG rating: 82 MW. For our system, at least 1xCTG, and 1xSTG are to be controlled...
scottf/
Appreciate your comment. Do you know how CT's magnetizing current will be changed if 60Hz CT is running on 50Hz? How will it affect protection settings?
rocmor/
Appreciate your comments.
By the way, I need to add a bit details of my case. That is, everything (system voltage, breaker's rated SC capacity, etc.) is the same except system frequency changing from 60Hz to 50Hz. Basically, I wonder what if a ANSI CB (60Hz) will be used on 50Hz...
Hello,
Do you have any idea what if ANSI circuit breaker (60Hz) will be used on a 50Hz power system?
I guess manufacturer declared short circuit duties (ANSI, 60Hz) should be derated on a 50Hz power system. If so, do you have any reference materials on this issues? I tried to search IEEE papers...
Hello,
I have CT & PT designed for 60Hz system and tested per ANSI/IEEE standards but those will be used on 50Hz power system.
If so, are there any advices on this issues? I guess CT & PT burden should be derated accordingly and CT saturation will be faster than the same CT in 60Hz. Did I...
Hello,
I have a situation to install 4.16kV, 600kVAR capacitor on the three (3) existing 2500HP motors and all three (3) 2500HP motors on the same bus for power factor improvement. For self-excitation, 600kVAR is selected below 90% of motor no load current (106A) due to self-excitation issue...
Waross// thanks for your advice.
I had also proposed zig-zag transformer application on the 11kV bus with HRG on each generator as well as hybrid grounding scheme for generator but my client does not want to have all those applications in the plant.
Basically, he does not allow us to install...
We have total six (6) GTGs (all 15 MVA, 11kV generators) and all generators will be connected to a common 11kV bus. i.e. all generators in parallel and individually grounded. We have initially selected 100A NGR for each generator without neutral switching device.
In addition, we also have two...
I really appreicate all of your advices and I agreed I was too worrying about it.
Just for your information, I have 50kA breakers and its calculated DC component was about 33 kA_dc at this time while breaking current is about to 22 kA. I cannot increase SC rating of breaker since I cannot find...
Dear davidbeach,
Thanks for your quick advice and it makes me more comfortable. Do you think it would be good idea to use the max. generator ouput (16 MVA)at 0 degree C with the given parameters at 42 degree.C for my short circuit current calculations?
Dear dpc,
The reason why I am worrying...
Hello,
I have 14.24 MVA rated synchronous generator driven by gas turbine and it is rated at 42 degree C and all parameters are given based on this temperature.
If this generator will be running at 0 degree C. of site ambient temperature, the generator can cover more kVA e.g. let say 16 MVA as...
