CLEARANCES



CLEARANCES upto 33 KV Voltage:

Classification of Voltage         (Refer I.E. Rule (1) (a)

i) Low Voltage                           Not exceeding 250 V

ii) Medium Voltage                    Not exceeding 650 V

iii) High Voltage                        More than 650 Volts & upto 33 KV

iv) Extra High Voltage               More than 33 KV

1.Clearances along/across the road and cross country                   (Refer I.E. Rule No. 77)

 

Voltage

 

Across the road

 

Along the road

Clearance other than along the road and across the road

if above Conductor

if insulated conductor

1. Low medium Voltage

19 ft
(5.791 m)

18 ft
(5.486m)

15 ft
(4.572m)

13ft
(3.963m)

2. High Voltage up to 11 KV

20 ft
(6.096 m)

19 ft
(5.791m)

15ft
(4.572 m)

13ft
(3.963m)

3. High voltage above 11 KV

20 ft
(6.096 m)

19 ft
(5.182m)

17 ft
(5.182m)

 

Note :

For extra high voltage lines, the clearance above ground shall not be less than 17' (5.182 metres) plus 1' (0.30 metres) for every 33000 volts or part thereof by which the voltage of the line exceed 33000 volts.

The minimum clearance along or across any steel shall not be less than 20 (0.096 metres)

2. Clearance from building 9refer I.E. Rule No. 79)

 Voltage

Vertical Clearance

Horizontal Clearance

1. Low Medium voltage and service line

8' (2.439 m)

4' (1.218 m)

2. a. For high voltage lines upto and including 11000 volts.

12' (3.658 m)

4'(1.219m)

b. For high voltage lines above 11000 upto and including 33000 volts

12'(3.658m)

6'(1.829m)

3. For extra high voltage line (For every additional 33000 volts or part thereof)

1'(0.305)

1'(0.305)

3. Clearance between lines of different voltage on same or independent supports

i) Between 66, 33 , 22, 11 KV, LT or Telephone line  and 66 KV lines 8'(2.439m)

ii) between 110, 66, 33,, 22, 11 KV , LT or Telephone lines and 110KV lines 9'(2.744m)

iii) Between all lines upto 220 KV or Telephone lines and 220 KV lines 5'(4.572m)

4. Clearance over the river

For navigable rivers, clearance to be fixed in relation to the tallest mas, in consultation.

With the concerned navigation authorities.

5. Tree clearance

i) For E.H.T. Lines all tall trees with 40' (12'.19 metres) on either side of the line and all tree which are falling or would fall, to be cut.

ii) All bush growth 20'(6.096metres) on either side to be completely cleared. Grafted fruit trees which will not grow tail may be left out.

iii) All branches or leaves which are width 3'(0.914metres) from the conductors, neutral and earth wires in case of L.T. line should be cut.

6. Clearance from supporting structure of another line

i) Low or medium voltage lines   4' (1.218 metres)

ii) High voltage lines  6'( 1.829 metres)

iii) Extra high voltage lines  9' (2.744 metres)

*****