MINIMUM SAFE DISTANCES BETWEEN CONDUCTORS OF DIFFERENT CIRCUITS, TELECOMMUNICATION LINES AND STAY WIRES
6.1         GENERAL

6.1.1    This section sets minimum safe distances for overhead electric lines to prevent conductors contacting other conductors, or stay wires, or approaching sufficiently close to cause a fault condition. This section also applies to telecommunications lines.

 

6.1.2    The requirements of this section do not apply to substations and generating stations and unless specifically identified, traction system conductors.

 

6.1.3    The distances specified in Table 7 do not apply where the conductors of all relevant circuits are insulated. In the case of any of the insulated conductors operating at a voltage in excess of 1 kV, the conductor, or bundle of conductors, shall include an earth screen.

 

6.1.4    Where two circuits of different voltage cross each other, are attached to the same support, or share spans, the conductors of the higher voltage circuit should be placed above those of the lower voltage circuit. Earth wires may be above power circuits.

 

6.1.5    Telecommunications lines shall always be below power circuits.

 

 

6.2         CONDUCTORS OF DIFFERENT CIRCUITS ON DIFFERENT SUPPORTS (UNATTACHED CROSSINGS)

 

6.2.1    Under still air conditions, the vertical distance between any conductor or telecommunications line of the lower circuit at minimum sag and any point to which a higher circuit conductor may sag under the influence of short time overload current and solar radiation shall not be less than specified in Table 7.

 

6.2.2     The minimum vertical distance to a traction system is 2 m.

 

TABLE 7           MINIMUM VERTICAL DISTANCES BETWEEN CONDUCTORS (unattached crossings)

 

	Minimum distance between
Higher voltage of either circuit	conductors (unattached crossing)
	(m)
Below 1 kV a.c.	0.6
1 kV to 33 kV a.c.	1.2
Exceeding 33 kV but not exceeding 66	1.8
kV a.c.
110 kV a.c.	2.4
220 kV and 270 kV d.c.	2.8
350 kV d.c.	4

TABLE 9           MINIMUM SAFE APPROACH DISTANCE LIMITS FOR PERSONS FROM EXPOSED LIVE PARTS (Where consent from the owner of the live parts has been obtained)

 

Circuit Voltage	Distance Limits
	(m)
Below 1 kV	0.5
11 kV	1.5
22 kV	2.0
33 kV	2.5
66 kV	3.0
110 kV	4.0
220 kV and above	6.0