Answer / deepak shrivastava

It should be less than or equal to 0.1 ohms.

Answer / muhammad abid ali shah

Accurate value of earth resistance for the instrument and electronic circuits is 0.02 ohm

Answer / anindya chitta bagchi

.005ohms,according to IS Code 1961

We have one 500KVA transformer. We have tested REF relay and commissioned. After one and half year, due to some ground fault in one of the DB circuit Transformer tripped by REF relay. What will be cause and remedy. Please advise?

1 Answers  

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For these 2 devices what their power ratings are ? 1) single phase : AC 220V & starting amps 3Amps (i.e. starting torque) and the stabilized amps 2A ... For deep freezer 2) single phase : AC 220V & starting amps 2.7Amps (i.e. including the starting torque of a CRT monitor) and the stabilized amps 1 Amps thanks

1 Answers  

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Why the ceiling fan has three blades, why not two,four or five?

4 Answers  

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Transformer Specification say 66/11KV, 23/27/35MVA OFDAN,what is OFDAN? we know ONAN,ONAF or OFAF

2 Answers   Siemens,

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why we are using auto transformer in sub station mostly???

2 Answers  

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How we can design a cable for a 3phase load.

1 Answers  

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how can we chack a capacitor in acircuit

2 Answers  

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Why LED light has advantage of rapid reflection ,although other lights alse reflect.? and this light is considered to be best for transmission usage in case of Free optics

0 Answers  

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we are having 110 Kv,250mA Electrostatic precipitators for coal fired boilers. what will be static voltage and current after discharge and what time it will remain before earthing?

0 Answers   Siemens,

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what u meant by shock ? whether it depends on voltage or current

12 Answers  

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When we have earthing mesh or underground earthing network in industrial plants, weather we have NT-S or NT-C-S kind of earthing system, so eventually weather we must use 4 or 5 wire in 400 volt level (For example 3×150+70 mm2 or 5×150 mm2) in this connection I would like to know exactly the paragraph of IEC or IEEE number

0 Answers   TATA,

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Give the topology of current amplifier with current shunt feedback?

0 Answers  

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