Recent content by Elecme

You may refer to NFPA 70 as well for swimming pool lighting and the necessary protection required. Elecme

There are two kvars that should be considered for any transformer: Fixed kvar and this is related to the magnitizing current Step kvar and this is dependant on the loading Such figures are almost known and available at manufactureres. Try [u]www.trafounion.com Elecme

You are mixing two grounding systems in one, and you now have two separate grounding paths. Even this may affect the operation of the circuit breakers. You really need to get an engineer (Specialist in grounding) to see and decide after Elecme

Jbartos: is it a must to have that redundant operation of the ventilation,cause i doughpt that it has to be . as you said. Elecme

I agree with Jbartos that the reason may be the capacitive charging in the transmission line but this is for scenario #2. As for scenario #1. For scenario #2, I belive you should check the step up scheme(transformer and circuit breaker) and take some measurements. Elecme

bigamp, you got a star. Can you eleborate more on your paragraph below "If the generator has to operate in parallel with others, it is a good idea to tie its neutral earthing system in with that of the other generator(s) so that only one generator neutral is ever earthed. This will still...

Is it a MUST that all MV (11kV) generators to be grounded through impedance? or can we connect a 11kV generator solidly to ground?...when do we need each type of the following grounding system: · SOLIDLY GROUNDING · LOW IMPEDANCE · MEDIUM IMPEDANCE · HIGH IMPEDANCE Elecme

Is it mandatory by the code to provide complete detection in high rise building with mixed activities (Library, theater, restaurants, offices etc.)or partial coverage is sufficient. Elecme

The following statement is written in IEEE - buff book Std 242 -1986:4.5 (1) Bus Undervolatge Protection "A time delay relay is normally used to enable it to ride through momentary dips, thus preventing nuisance operation. An instantaneous undervoltage relay with its contact connected in...

Why sometimes it is preferred to use instantaneous undervoltage relay with a time delay one in bus protection? Elecme

Do we have to ground the MV (11kV)deisel generators through impedance ?.... and what is the difference between high, low impedance and solidly earthing rather than the limitation of the fault current and the interruption at 1st or 2nd fault......etc. Elecme

I am very interested in small power plants, composed of number of generators synchronizing switchgear and the like. I am talking about a specific job, which is providing an industrial area with a power estimate of 12 MVA with such a small power plant. I have the following inquiries: What is the...

can you elaborate more about the 1st point? Elecme

Can some advise, whay the iron core of the transformers is earthed? Elecme

I am talking about light load, which means lesser current. Elecme