SELECTION OF CABLE TRUNKING

1. 50 x 50 mm G.I TRUNKING

(A)Total capacity units as per the manufacturer's catalogue 1037.00(B) Occupation factor as commented by the Consultants 570.35 (ie,1037*55% =570.35)

Sl.No Wire size No.of circuits No.of wires Total factor

1 2.5sqmm 8 24 11.4 273.6

2 4sqmm 6 18 15 270

Total 543.6Total factor from the above table is 543.6 which is less than item B( ie 570.35)So,50mm x 50mm G.I.Trunking will be used for laying of 8 nos lighting circuits and

and 6 nos power circuits wires.

2. 75 x 75 mm G.I TRUNKING

(A)Total capacity units as per the manufacturer's catalogue 2371.00(B) Occupation factor as commented by the Consultants 1304.05 (ie,2371 x 55%=1304.05)For example,If 18Nos. of lighting circuits and 15Nos. Power circuits area to be laid on the above trunking,

then the calculation will be as follows,

Sl.No Wire size No.of circuits No.of wires Total factor

1 2.5sqmm 18 54 11.4 615.62 4sqmm 15 45 15 675

Total 1290.6Total factor from the above table is 1290.6 which is less than item B( ie 1304.05)So,75mm x 75mm G.I.Trunking will be used for laying of 18 nos lighting circuits and and 15 nos power circuits wires.

For example,If 8Nos. of lighting circuits and 6Nos. Power circuits area to be laid on the above trunking, then the calculation will be as follows,

Recommended factor per wire

Recommended factor per wire

2. 100 x 100 mm G.I TRUNKING

(A)Total capacity units as per the manufacturer's catalogue 4252.00(B) Occupation factor as commented by the Consultants 2338.6 (ie,4252 x 55%=2338.6)For example,If 18Nos. of lighting circuits and 15Nos. Power circuits area to be laid on the above trunking,

then the calculation will be as follows,

Sl.No Wire size No.of circuits No.of wires Total factor

1 2.5sqmm 34 102 11.4 1162.82 4sqmm 26 78 15 1170

Total 2332.8Total factor from the above table is 2332.8 which is less than item B( ie 2338.6)So,100mm x 100mm G.I.Trunking will be used for laying of 34 nos lighting circuits and and 26 nos power circuits wires.

From the above tables the selection will be followed based on the following table

SL NO. Total factor

1 50 x 50 mm 1037 570.35 8 6 543.6

2 75 x 50 mm 1555 855.25 14 8 838.8

3 75 x 75mm 2371 1304.05 18 15 1290.6

4 100 x 75 mm 3189 1753.95 24 20 1720.8

5 100 x 100mm 4252 2338.6 34 26 2332.8

6 150 x 75mm 4742 2608.1 36 30 2581.2

7 150 x 100mm 6394 3516.7 46 42 3463.2

8 150 x 150mm 9697 5333.35 72 62 5252.4

Recommended factor per wire

Trunking size

Total factor considering 45% spare capacity

No of lighting cirucuits

No of power circuits

Total factor considering 45% spare capacity in

relation to No of circuits