When we use air circuit breaker, it has O/L protection ,time delay SC protection, Instataneous SC protection & ground fault protection. They all have some setting range. But what is the suitable/allowable setting for the above protection which will be safe for the equipment? For example-O/L protection setting have a range of (0.4,0.45,0.5,0.55,0.6,0.65,0.7,0.8,0.9,1.0)xIn Time delay SC protection have a range of (1.25,1.5,2,3,4,6,8,10,12)xIn Time delay setting is 0.02,0.1,0.2,0.3,0.4 Instataneous setting is fixed to 20xIn Gound fault setting is given 100A,300A,600A,900A,1200A This setting are for 2500A ACB. So what will be the basic allowable setting for the above protection? is there any formulae to calculate this<
2155Why the meters sonnected to metering core of CT are not damagedon event of a fault??? Explain the phenomena??
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TCS,
1 4221Why the Transformer connection is changing in different transformer?(Like Star & Delta,Delta & Delta,Star & Star,Delta Star) From that connection where it is used?
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2 4905What will happen when more than one star neutral points at same voltage level are connected to earth by metallic conductor?
TCS,
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2 5057Classical power system stability was mainly focussed on rotor angle stability but modern power system stability has more focus on voltage stability.Why?
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