Electrical Safety Clearance for Electrical Panel
August 26, 2012 11 Comments
Electrical Safety Clearance for Electrical Panel:
Working Space around Indoor Panel/Circuit Board (NES 312.2):
|
Voltage |
Exposed live parts to Not live parts( or grounded parts ) | Exposed live parts to Grounded parts (concrete, brick, and walls). | Exposed live parts on both sides |
|
Up to 150 V |
0.914 Meter (3 Ft) |
0.914 Meter (3 Ft) |
0.914 Meter (3 Ft) |
|
150 V to 600 V |
0.914 Meter (3 Ft) |
1.07 Meter (3’6”) |
1.22 Meter (4 Ft) |
Clearance around an Indoor electrical panel (NES 110.26):
|
Description of Clearance |
Distance (min) |
| Left to Right the minimum clearance |
0.9 Meter (3 Ft) |
| Distance between Panel and wall |
1.0 Meter |
| Distance between Panel and Ceiling |
0.9 Meter |
| Clear Height in front of Panel>480V |
2.0 Meter |
| Clear Height in front of Panel <480V |
0.9 Meter (3 Ft) |
| Clearance When Facing Other Electrical Panels < 480V |
0.9 Meter (3 Ft) |
| The width of the workingspace in front of the Panel |
The width of Panel or 0.762 Meter which is Greater. |
| Headroom of working spaces for panel boards (Up to 200Amp) |
Up to 2 Meter |
| Headroom of working spaces for panel boards (More than 200Amp &Panel height is max 2 Meter) |
Up to 2 Meter( If Panel height is max 2 Meter) |
| Headroom of working spaces for panel boards (More than 200Amp &Panel height is more than 2 Meter) |
If Panel height is more than 2 Meter than clearance should not less than panel Height |
| Entrance For Panel (More than 1200 Amp and over 1.8 m Wide) |
One entrance required for working space (Not less than 610 mm wide and 2.0 m high ) |
| Personal Door For Panel (More than 1200 Amp) |
Personnel door(s) intended for entrance to and egress from the working space less than 7.6 m from the nearest edge of the working space |
| Dedicated Electrical Space. |
Required Space is width and depth of the Panel and extending from the floor to a height of 1.8 m (6 ft) above the equipment or to the structural ceiling, whichever is lower |
| The door(s) shall open in the direction of egress and be equipped with panic bars, pressure plates, or other devices that are normally latched but open under simple pressure |
|
| the work space shall permit at least a 90 degree opening of equipment doors or hinged panels |
|
Clearance for Conductor Entering in Panel (NES 408.5):
|
Description of Clearance |
Distance (min) |
|
Spacing between The conduit or raceways(including their end fittings) and Bottom of Enclosure |
Not rise more than 75 mm (3 in) above the bottom of the enclosure |
|
Spacing Between Bottom of Enclosure and Insulated bus bars, their supports, |
200 mm |
|
Spacing Between Bottom of Enclosure and Non insulated bus bars |
200 mm |
Clearance between Bare Metal Bus bar in Panel (NES 408.5):
|
Voltage |
Opposite PolarityMounted on Same
Surface |
Opposite PolarityWhere Held Free in Air | Live Parts to Ground |
| Up to 125 V | 19.1 mm | 12.7 mm | 12.7 mm |
| 125 V to 250 V | 31.8 mm | 19.1 mm | 12.7 mm |
| 250 V to 600 V | 50.8 mm | 25.4 mm | 25.4 mm |
Clearance of Outdoor electrical panel to Fence/Wall (NES 110.31):
|
Voltage |
Distance (min) |
| 600 V to 13.8 KV |
3.05 Meter |
| 13.8 K V to 230 KV |
4.57 Meter |
| Above 230 KV |
5.49 Meter |
Working Space around Indoor Panel/Circuit Board (NES 110.34):
|
Voltage |
Exposed live parts to Not live parts( or grounded parts ) | Exposed live parts to Grounded parts (concrete, brick, and walls). | Exposed live parts on both sides |
|
601 V to 2.5 K V |
0.914 Meter (3 Ft) |
1.2 Meter (4 Ft) |
1.5 Meter (5 Ft) |
|
2.5 K V to 9.0 K V |
1.2 Meter (4 Ft) |
1.5 Meter (5 Ft) |
1.8 Meter (6 Ft) |
| 9.0 K V to 25 K V |
1.5 Meter (5 Ft) |
1.8 Meter (6 Ft) |
2.5 Meter (8 Ft) |
| 25 K V to 75 K V |
1.8 Meter (6 Ft) |
2.5 Meter (8 Ft) |
3.0 Meter (10 Ft) |
|
Above 75 KV |
2.5 Meter (8 Ft) |
3.0 Meter (10 Ft) |
3.7 Meter (12 Ft) |
Clearance around an Outdoor electrical panel (NES 110.31):
|
Description of Clearance |
Distance (min) |
| Clear work space: | Not less than 2.0 Meter high(Measured vertically from the floor or platform) or not less than 914 mm (3 ft) wide (Measured parallel to the equipment). |
| Entrance For Panel (More than 1200 Amp and over 1.8 m Wide) | One entrance required for working space (Not less than 610 mm wide and 2.0 m high ) |
| Entrance For Panel: On Large panels exceeding 1.8 Meter in width | One Entrance at each end of the equipment. |
| Nonmetallic or Metal-enclosed Panel in general public and the bottom of the enclosure is less than 2.5 m (8 ft) above the floor or grade level | Enclosure door or hinged cover shall be kept locked. |
Elevation of Unguarded Live Parts above Working Space (NES 110.34E):
|
Voltage |
Elevation (min) |
| 600 V to 7.5 KV |
2.8 Meter |
| 7.5 K V to 35 KV |
2.9 Meter |
| Above 35 KV |
2.9 Meter + 9.5 mm/KV |
Working Space for Panel (Code Georgia Power Company):
|
Voltage |
Exposed live parts to Not live parts( or grounded parts ) | Exposed live parts to Grounded parts (concrete, brick, and walls). | Exposed live parts on both sides |
|
Up to 150 V |
3.0 Meter |
3.0 Meter | 3.0 Meter |
|
150 V to 600 V |
3.0 Meter | 3.5 Meter | 4.0 Meter |
|
600 V to 2.5 KV |
3.0 Meter | 4.0 Meter | 5.0 Meter |
|
2.5 KV to 9 KV |
3.0 Meter | 5.0 Meter | 6.0 Meter |
|
9 KV to 25 KV |
5.0 Meter | 6.0 Meter | 6.0 Meter |
JIGNESH PARMAR
Thank You!!!
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in indian context we need that clearence as per IE rule or IS or IEC. Please reallign the document as per these codes/practises. Wecan not refer NES or equiv
NES is abbreviated as ?
National environmental standards for electricity transmission activities,NZ
can you please relevant codes in India
Dear Sir,
Is there any Indian standard which gives clearances for panels…! Does Indian Electricity Rules give any info regarding as it would be easy to convince the clients for approval……!
hai sir,
I juzz want to ask u had how does a LT circuit breaker trips on single phasing
thank for your valuable information
Dear sir,
what will be the minimum clearance between back wall and panel if panel is not back opening.
can u tell me the standard(IS/IEC) Were i got all these clearance.
what should be the clearance(verical,horizonotal) between two adjacent MCCBs.If two MCCBs touch each other what is the derartng factor to apply.
If the panel has all front access , then backside to wall clearance is required?