-
A three phase line has conductor of 5 mm diameter placed at the corner of an equilateral triangle of 1.5 m side. The capacitive reactance to netural per phase per km will be
-
- 1.25 × 106 Ω/km
- 8.68 × 105 Ω/km
- 4.25 mΩ/km
- 3.66 × 105 Ω/km
Correct Option: D
Here, d = 5 mm, r = 2.5 mm = 2.5 × 10-3m, D = 1.5 m
∴ Deq = (DAB. DBC. DCA)1/3
= (1.5 × 1.5 × 1.5)1/3 = 1.5 m
| Cn = | = | |||||||
| 18 × 109 × In |  |  | ||||||
| = | |||||
| 18 × 109 × In | | | |||
= 8.68 × 10-12F/m
= 8.68 × 10-9F/km
= 8.68 × 10-3µF/km
Capacitive reactance,
| XC = | ||
| 2πƒ(Cn) |
| = | ||
| 2π × 50 × 8.68 × 10-9 |
= 3.66 × 105 Ω/km
