Electrical Safety Clearance (Northern Ireland Electricity) (Part-3)
August 10, 2012 10 Comments
Standard: Northern Ireland Electricity (NIE), 6/025 ENA
Clearances of Electrical Line to Ground and Roads:
| Description of Clearance |
0.4 KV |
11 KV |
33KV |
110KV |
220 KV |
400KV |
| Line conductor to any point not over road |
5.2 Meter |
6.1 Meter |
6.4 Meter |
6.4 Meter |
7.0 Meter |
7.0 Meter |
| Line conductor to road surface |
5.8 Meter |
6.1 Meter |
6.4 Meter |
6.4 Meter |
7.4 Meter |
8.1 Meter |
| Line conductor to road surface of high load routes |
6.9 Meter |
6.9 Meter |
6.9 Meter |
7.2 Meter |
8.5 Meter |
9.2 Meter |
| Bare live metalwork ( transformer terminals, jumper connections, etc) |
4.6 Meter |
4.6 Meter |
4.6 Meter |
– |
– |
– |
Clearances of Electrical Line to Other Objects:
| Description of Clearance |
<11 KV |
33 KV |
110KV |
220KV |
400 KV |
| Line conductor or bare live metalwork to any object that is normally accessible (including permanently mounted ladders and access platforms) or to any surface of a building |
3.0 Meter |
3.0 Meter | 3.4 Meter | 4.6 Meter | 5.3 Meter |
| Line conductor or bare live metalwork to any object to which access is not required AND on which a person cannot stand or lean a ladder |
0.8 Meter |
0.8 Meter | 1.2 Meter | 2.4 Meter | 3.1 Meter |
| Line conductors to irrigates, slurry guns and high-pressure hoses |
30 Meter |
30 Meter | 30 Meter | 30 Meter | 30 Meter |
| Line conductors to playing fields |
8.5 Meter |
8.5 Meter | 8.5 Meter | 8.5 Meter | 8.5 Meter |
| Line conductors to Caravan Sites |
9.0 Meter |
9.0 Meter | 9.0 Meter | 9.0 Meter | 9.0 Meter |
| Horizontal clearances to wells |
15.0 Meter |
15.0 Meter | 15.0 Meter | 15.0 Meter | 15.0 Meter |
Clearances of Electrical Line to Trees and Hedges:
| Description of Clearance |
<11 KV |
33 KV |
110KV |
220KV |
400 KV |
| Line conductor or bare live metalwork to trees or hedges unable to support a ladder or being climbed. |
0.8 Meter |
0.8 Meter | 1.2 Meter | 2.4 Meter | 3.1 Meter |
| Line conductor or bare live metalwork to trees or hedges capable of supporting a ladder or being climbed. |
3.0 Meter |
3.0 Meter | 3.4 Meter | 4.6 Meter | 5.3 Meter |
| Line conductor or bare live metalwork to trees falling towards the overhead line with the line conductors hanging vertically. |
0.8 Meter |
0.8 Meter | 1.2 Meter | 2.4 Meter | 3.1 Meter |
| Line conductors to trees in Orchards |
3.0 Meter |
3.0 Meter | 3.4 Meter | 4.6 Meter | 5.3 Meter |
Clearances of Electrical Line to Street Lighting:
| Description of Clearance |
0.4 KV |
11 KV |
33KV |
110KV |
220 KV |
400KV |
| Line conductor to Lantern on same pole |
1.0 Meter |
– |
– |
– |
– |
– |
| Bare line conductor to lantern or column below. |
1.5 Meter |
– |
– |
– |
– |
– |
| Insulated line conductor to column | 0.3 Meter |
– |
– |
– |
– |
– |
| Insulated line conductor to lantern | 1.0 Meter |
– |
– |
– |
– |
– |
| Column to nearest LV pole | 1.5 Meter |
– |
– |
– |
– |
– |
| Line conductor to street lighting column with |
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|
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| (i) Column in normal upright position. | – | 1.7 Meter | 1.7 Meter | 2.3 Meter | 3.3 Meter | 4.0 Meter |
| (ii) Column falling towards line with line conductor hanging vertically only | – | 1.7 Meter | 1.7 Meter | 2.3 Meter | 3.3 Meter | 4.0 Meter |
| (iii)Column falling towards line | – | 0.4 Meter | 0.4 Meter | 0.8 Meter | 1.4 Meter | 1.9 Meter |
Clearances of Electrical Line to Waterways:
| Description of Clearance |
0.4 KV |
11 KV |
33KV |
110KV |
220 KV |
400KV |
| Navigable Waters: Lower bank to conductor or earth wire |
10.5 Meter |
10.5 Meter | 10.5 Meter | 10.5 Meter | 10.5 Meter | 10.5 Meter |
| Minor Watercourses : Lower bank to conductor or earth wire |
7.6 Meter |
7.6 Meter | 7.6 Meter | 7.6 Meter | 7.6 Meter | 7.6 Meter |
Clearances to Railways:
| Description of Clearance |
0.4 KV |
11 KV |
33KV |
110KV |
220 KV |
400KV |
| Line conductor to ground level |
6.1 Meter |
6.1 Meter | 6.1 Meter |
6.7 Meter |
7.0 Meter |
7.6 Meter |
| Line conductor to ground level on or across vehicle parks | 7.6 Meter | 8.5 Meter | 8.5 Meter | 9.1 Meter | 9.4 Meter | 10.1 Meter |
| Line conductor to ground level at roads and yards, where road mobile cranes are likely to be employed | 10.7 Meter |
10.7 Meter |
10.7 Meter |
11.2 Meter |
11.5 Meter |
12.2 Meter |
| Line conductor to Rail level | 7.3 Meter | 7.3 Meter | 7.3 Meter | 8.0 Meter | 8.2 Meter | 8.8 Meter |
| Line conductor to the level of buildings, gantries or other structures (including those carrying traction wires) on which a man may be | 3.0 Meter | 3.0 Meter | 3.0 Meter | 3.7 Meter | 4.6 Meter | 6.1 Meter |
| Line conductor to poles and other projections. | 2.4 Meter | 2.7 Meter | 2.7 Meter | 3.0 Meter | 3.7 Meter | 5.5 Meter |
| Line conductor to any other wire other than traction wires. | 1.8 Meter | 1.8 Meter | 1.8 Meter | 2.4 Meter | 3.0 Meter | 3.7 Meter |
Clearances of Electrical Line to Fuel Tanks:
|
Description of Clearance |
0.4 KV |
11 KV |
33KV |
110KV |
220 KV |
400KV |
| Horizontal clearance from line conductors to petrol tanks and vents |
15 Meter |
15 Meter |
15 Meter |
15 Meter |
15 Meter |
15 Meter |
| Horizontal clearance from line conductors to liquid gas tanks |
|
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|
|
|
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| (1) 459 to 2273 litre capacity |
3.0 Meter |
3.0 Meter |
3.0 Meter |
3.4 Meter |
4.6 Meter |
5.3 Meter |
| (2) 2274 to 9092 litre capacity |
7.6 Meter |
7.6 Meter |
7.6 Meter |
7.6 Meter |
7.6 Meter |
7.6 Meter |
| (3) More than 9093 litre. |
15 Meter |
15 Meter |
15 Meter |
15 Meter |
15 Meter |
15 Meter |
| Vertical clearance from line conductors to fuel oil tanks |
Please refer Clearances to Objects |
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Clearances of Electrical Lines to other Electrical Lines:
|
Description of Clearance |
0.4 KV |
11 KV |
33KV |
110KV |
220 KV |
400KV |
| Lowest line conductor or earth wire of upper line to highest line conductor of lower line. |
1.0 Meter |
1.8 Meter |
2.0 Meter |
2.5 Meter |
3.7 Meter |
4.4 Meter |
| Lowest line conductor or earth wire of upper line to earth wire of lower line where erected. |
0.7 Meter |
1.4 Meter |
1.6 Meter |
2.5 Meter |
3.7 Meter |
4.4 Meter |
| Lowest line conductor or earth wire of upper line to any point on a support of the lower line on which a person may stand. |
2.7 Meter |
2.8 Meter |
3.0 Meter |
3.4 Meter |
4.6 Meter |
5.3 Meter |
| Support of upper line and any conductor of lower line. |
7.5 Meter |
7.5 Meter |
7.5 Meter |
15 Meter |
15 Meter |
15 Meter |
Vertical Passing Clearance (sites where vehicles will pass below the lines):
| Description of Clearance |
<33 KV |
110KV |
220KV |
400 KV |
|
Passing clearance: fixed height loads |
0.8 Meter | 1.4 Meter | 2.4 Meter | 3.1 Meter |
|
Passing Clearance: variable height loads. |
2.3 Meter | 3.2 Meter | 4.1 Meter | 5.0 Meter |
Horizontal Clearance (sites where there will be no work or passage of plant under lines):
| Description of Clearance |
<33 KV |
110KV |
220KV |
400 KV |
|
Minimum horizontal distances to safety barriers |
6.0 Meter |
9.0 Meter | 12.0 Meter | 14.0 Meter |
Distance between Conductors of Same/Different Circuit (On Same Support):
| Higher Voltage of either Circuit |
Lower Voltage of either Circuit |
Distance between Circuits |
|
< 33 KV |
< 1 KV |
1.0 Meter |
|
< 33 KV |
> 1 KV |
1.2 Meter |
|
33 KV to 110 KV |
< 1 KV |
1.5Meter |
|
33 KV to 110 KV |
> 1 KV |
2.0 Meter |
|
Above 110 KV |
All |
2.5 Meter |
Vertical Distance between Conductors of different Circuit (On Different Support):
| Higher Voltage of either Circuit |
Distance between Circuits |
|
< 1 KV |
0.6 Meter |
|
1 KV to 33 KV |
1.2 Meter |
|
33 KV to 66 KV |
1.8 Meter |
|
110 KV |
2.4 Meter |
|
220 KV |
2.8 Meter |
Distance between Conductors (Taken down from Pole to other Support, on Transformer):
| Voltage |
Distance between Circuits |
|
11 KV & LV Line |
0.60 Meter |
|
22 KV & LV Line |
0.75 Meter |
|
33 KV & LV Line |
0.90 Meter |
Horizontal Distance of Telecommunication Line & Overhead Line:
| Description of Clearance |
Distance |
| Telecommunication Line(Not insulated) to HV Line |
Min 1.6 Meter |
| Telecommunication Line (Bare) to LV (Bare) Line | Min 1.2 Meter |
| Telecommunication Line (Covered) to LV (Bare) Line | Min 0.6 Meter |
| Telecommunication Line (Bare) to Stay (Bare) Wire | Min 0.3 Meter |
Passage Way for Metal clad Switchgear:
| Description of Clearance |
Distance |
| Clean &unobstructed Passages at the front of any Low/High Voltage Switchgear. |
1.0 Meter wide & 2.5 Meter high |
| Clean &unobstructed Passages at side or under any earthed enclosure containing Bare Conductor | 0.8 Meter wide & 2.2 Meter high |
Safe approach distance for Person from Exposed Live Parts:
| Circuit Voltage |
Distance |
| < 1 KV |
0.5 Meter |
| 11 KV |
1.5 Meter |
| 22 KV |
2.0 Meter |
| 33 KV |
2.5 Meter |
| 66 KV |
3.0 Meter |
| 110 KV |
4.0 Meter |
| >220 KV |
6.0 Meter |
JIGNESH PARMAR
Hi, Nice article once again. Please post an article on different Transmission line tower designs & their differences.(5 degree,7 degree…?). Also if it is possible to design a tower to carry two
different voltage levels. any examples of that.
Thank you
– Manish Deshmukh
very useful notes
Dear Sir,
your notes are excellent and usefull to me. Please give me the clearance between underground oil pipeline and a 400kV overhead transmission line.
Regards
Dear Sir,
This is nice one . i want to know what will be mini. distance distance of a indoor panel from wall & other panel infornt of that .
Thank you so much for all your notes here. They are really useful to all electrical engineers.
hi..please give me a solution. i have a land of 8 cents in city. have a lorry weighbridge for which i have e.b connection. behind it i have constructed two houses with an height of 11 feet. above the building passes 110 kv line. it is around 30 feet from terrace. omy application for e.b connection for that building has been rejected due to the line passing above. its been four years now. it has the vertical clearance but not horizontal.. please kindly suggest me a solution.
Please mention all clause of IE & IS norms in all clearance
Already given in the Blog !!! Refer Past Posts…
Hi Jignesh,
I am buying a flat and there are couple of high tension wires near the plot. I wanted to know the safe distance to reside from an overhead high tension wire of 220KV and another of higher value. I also have concern about the EMF effects of HT lines. Please provide your thoughts.
Thanks,
–Basant
Dear Mr.Jignesh
We have encounter a problem with finding safety horizontal distance to High capacity oil (diesel/Gasoline) Tanks(capacity of 12500-13000 MT) from High voltage lines. In this note you have specified about 15m clearance to tanks above 9093 Litre. Can we apply same for high capacity oil tanks?
You have mentioned the referred standard as “Northern Ireland Electricity (NIE), 6/025 ENA”. I have tried my best to find this but couldn’t. Please be kind enough to upload the relevant standard send to via email. My email is ” ishannivanka@gmail.com”
Thank you very much and highly appreciate your passion to educate us on these areas.