Answer / vg

to limit the earth fault current generator/Alternator NGR design. ex. for 11KV generator Earth Fault Current to be limit on 100 Amp.
V=I*R
R=V/I
so I=11000/1.732*100=63.5Ohms.
11KV generator NGR 63.5 amps for 100 Amp fault current.

Lux meter is the measuring device to measure the lux level of lighting fixture. in industrial sector two types of lighting fixture is being used as street lighting purpose 1. HPSV (Sodium) and 2. HPMV (Mercury). HPMV having white light which is an combination of red, blue and yellow colour, while HPSV haivng Yellow lighting. in HPSV red & blue colour will be absent. during measurement of the lux level of HPSV and HPMV fixture. 1. Lux meter can measure the actual lux level of both fixture? 2. or it will show false reading for HPSV fixture light as it has only yellow light present. please give me answer

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