In directional earth fault protection for generator, one
core balance CT is for residual current, what other CT is
for, which is placed on neutral?
- 2 Answers
- 3689 Views
- I also Faced
- E-Mail Answers
Answer Posted / k.prakashchandra
For balancing the unbalanced current of the phases . If
there is balancing ,there is no earth fault within the gen
| Is This Answer Correct ? | 0 Yes | 1 No |
Post New Answer View All Answers
advantage and disadvantage of team work?
1. A 380 / 220 V r.m.s. 3-phase 4-wire circuit carries loads of 8 + j8.1 ohm; 4 + j4.1 ohm; and 2 +j2.1 ohmin the three phases respectively. The length of the circuit is 100 m, and the resistivity of the phase conductors is 0.0005 Ω/m. The neutral conductor is of the same size as the phase conductors. a) Select a reference angle 0for the first phase. Then write down the three phase voltages in both polar format and complex number format. b) Make appropriate assumptions, and take temperature effects on resistance is insignificant. Calculate the currents in the three phases. (Note: Determine conductor resistance, and apply Kirchhoff’s Voltage Law) Based on the result, suggest a main switch rating for the circuit. c) Show your preferred direction of neutral current in a diagram, and then determine its value. (Note: Apply superposition principle, and Kirchhoff’s Current Law) Use its magnitude to show that in this circuit, the unbalanced load may increase the voltage drop in some of the phases. (Note: Also observe the common volt drip in neutral) State your assumptions, if there are any. d) Suddenly the neutral wire of the circuit is broken. Estimate the new currents in the first phase, i.e. Phase L1. State your assumptions, if there are any.
mccb service sittings be done?
Why arc quenching is used in Diode ?
What is the relationship between voltage,current & frequency?
diameter of cable and core is doubled then the value of capacitance is
what is the concept of directional power?
What happened when capacitor connect series in ac circuit?
What do you mean by a phase angel of instrument transformer?
What is transient Phenomenon?
in the directional overcurrent and earthfault protection,normally we are setting the angle 45 deg lead for phase fault overcurrent and -45 deg lead for earthfault fro forward direction.but both the fault are operating on the same angle region only.why?how the relay will response?
What is the difference between circuit breaker and isolator
formula for calculation of switchgears(i.e. contactor, fuse, cb, relay etc.), if load current is given?
When is lag lead compensator is required?
why starting current is high and resistance is almost 0 during the starting of motor dc motor...?
