Quick Reference -Earthing

Hot dip galvanization. (IS 2629)

Galvanizing

Minimum thickness:

Min. weight:

MS flats 5mm thick & over

75 microns (minimum)

610 gms. / sq. mtr.

MS flats under 5mm thickness

60 microns (minimum)

460 gms. / sq. mtr.

Pipes/ conduits with thickness  & over 5 mm

75 microns (minimum)

610 gms. / sq. mtr

Pipes/ conduits with thickness under 5mm

60 microns (minimum)

460 gms. / sq. mtr

GI Wire

20 Microns (Medium coated)

150 gms. / sq. mtr.

OVERLAPING OF EARTHING STRIP

Size of Earthing Strip

Minimum Over Laping

20×3

20MM

20×6

20MM

25×3

25MM

25×6

25MM

32×6

25MM

40×5

50MM

40×6

50MM

50×6

50MM

50×10

50MM

75×6

50MM

75×10

50MM

NO’S AND SIZE OF NUT BOLT FOR JOINTING EARTHING STRIP

Size of Earthing Strip

Minimum Nut Bolt Required

Minimum Size of Nut Bolt

20×3

2 NO’S

8X25MM

20×6

2 NO’S

8X25MM

25×3

2 NO’S

8X25MM

25×6

2 NO’S

8X25MM

32×6

2 NO’S

8X25MM

40×5

4 NO’S

8X25MM

40×6

4 NO’S

8X25MM

50×6

4 NO’S

10X25MM

50×10

4 NO’S

10X25MM

75×6

4 NO’S

10X25MM

75×10

4 NO’S

10X25MM

Weight of G.I. wire  (Steel Tube India)

Gauge Gms.

mm

Weight Kg / Meter.

4

5.892

0.216

6

4.876

0.148

8

4.064

0.103

10

3.251

0.066

12

2.641

0.045

14

2.032

0.026

16

1.625

0.017

Weight of G.I Flat Strip

Sizes in (HxW)

Kgs/Per meter

Application

20×3 mm

0.49

Lighting Arrestor

20×6 mm

0.98

PLC Panel

25×3 mm

0.6

25×5 mm

0.97

25×6 mm

1.3

Control & Relay Panel

32×5 mm

1.21

Lighting Panel & Local Panel

32×6 mm

1.625

Distribution Board

40×3 mm

0.964

Motors 5.5kw-55Kw

40×5 mm

1.476

40×6 mm

1.92

HT switchgear, structures, cable trays & fence, rails, gate and steel column

50×3 mm

1.28

50×5 mm

1.92

50×6 mm

2.56

50×10 mm

4

Transformers Substations

62×6 mm

3.07

65×10 mm

5.2

75×10 mm

6

75×12 mm

7.2