slavag,
Not sure if I am following your concerns correctly. I think that ultimately it would require a better overview of this situation (schematics) to come to a clear understanding of this situation.
clos
As cbradley mentioned this is a Distribution Substation, a utility I assume. I doubt that there are any motors being fed in this substation and furthermore this substation is probably comprised of outbound feeder bays only.
Now look at it this way cbradley, I am not aware of what kind of...
If the upstream source that is feeding both the normal and emergency bus is the same then there would no possiblity to synch out of phase. I am assuming that is why you mentioned no synch check relay in your question. Therefore if the basic throw-over scheme is just an under-voltage condition...
Just trying to get a feel for what is out there....For a typical combined or simple cycle power plant (138kV-500kV) what are typical distances between the plant (GSU HV terminals) and switchyard (CBs in corresponding configuration; double breaker, breaker and half, etc)? Max distance anyone has...
Hello Svetozar,
Not sure from who or where you acquired your PAS. In any case, you can try contacting Siemens PT&D in either Nuerenberg Ger. or Wendell U.S.A. They have the PAS expertise that could resolve your issue.
Regards,
clos
As was mentioned above in previous threads, if this about efficiency of A) [Rankine cycle power plant output – transmission/distribution system losses – electric car losses] vs. B) [Otto engine powered automobile output (Wankel engine for you Mazda fans)] then the winner is system A.
If this...
Yes that is correct slavag...
By the way, you say that you had a similar situation occur and your motors were tripping on unbalance protection. If you were backfeeding motors via the GSU and Unit Aux Tfr, with GCB open, and a single pole on your upstream switchyard CB did not open, why didn’t...
This is a hypothetical scenario considering that there is no protection is in place to prevent the following:
While backfeeding a combined cycle power plant via the GSU [HS (System Side) connected in Wye and LS (Gen Side) in Delta] the upstream switchyard breaker opens but only:
a) 1 pole...
It was a Non-Unionized Protection and Control Engineer. Responsible for P&C commissioning, maintenance, and trouble shooting of all P&C substation related equipment.
Dade County P&C guys had their laptops confiscated by the government the next day.
FPL still doing full sequence of events...
Slavag,
Understood. I did not mention that we are also implementing secondary generator protection (Siemens 7UM621). This would be the back-up that you are referring to. Both the Beckwith M-3425A and the Siemens 7UM621 will cover the same protective elements i.e. 59N, 27TN. Given this...
raghun,
I think you’re right on with your assumptions. I was leaning towards your explanation but I wanted some confirmation. The area (zone) of protection changes as soon as the GCB is open and the 59N element from the generator protection (i.e. Beckwith M-3425A) is lost and the unit is...
Can anyone differentiate the philosophy behind tripping on 59N vs. alarming on a 59N?
Factors for consideration include:
This is in a Combustion Turbine Generating Unit.
VT on the LV side of the Generator Step Up Tx (after the Generator circuit breaker) is providing the open delta potential...
Can anyone see any other drawbacks to using a Circuit Breaker instead of a contactor. This is being considered for MV switchgear application feeding a 3000hp Gas Turbine Motor starter. Other than a contactors ability to withstand wear and tear what other pros are there to using a contactor in...