Technical Specifications


Current Rating of Copper Busbars


Note: Rating apply for single bars on edge operating in a 40C ambient temperature with 50C temperature rise. The give ac rating are for frequencies up to 60 Hz. When number of conductors are used in parallel, the total current capacity is less than the rating for a single bar times the number of bus used. This is due to obstruction to convection and radiation losses from the inner conductors. To facilitate the making of interleaved joints, the spacing between laminated bars is often made equal to the thickness.

Dimensions for Cable Glands

Eg:- For 6mm thick bars up to 100mm wide , mounted on edge with 60mm spacing between laminations, the isolated bar rating may be multiplied by the above factors to obtain the total rating.

New Harmonised Color Code According to BS 7671
 

CONDUCTOR GAUGE TABLE
Size of conductor
Nominal Diameter
Nominal Cross - sectional
AWG
mm
Area mm
40
0.079
0.0048
38
0.102
0.0081
36
0.127
0.0127
32
0.203
0.0324
30
0.254
0.0507
29
0.287
0.0647
28
0.320
0.0804
27
0.361
0.102
26
0.404
0.128
25
0.455
0.162
24
0.511
0.205
23
0.574
0.259
22
0.643
0.324
21
0.724
0.412
20
0.813
0.519
19
0.912
0.653
18
1.02
0.823
16
1.29
1.31
14
1.63
2.08
12
2.05
3.31
10
2.59
5.261
8
3.27
8.367

Graphics Symbol for Circuits Diagrams
Useful Electrical Circuits Diagrams
1. Motor contactors Direct-on-line Starting - Diagram
2. Motor contactors Changeover via -STOP - Diagram
3. Motor contactors Direct-on-line Starting Contacts Fitted & Example- Diagram
4. Power Distribution Systes- How to Select the Number of Circuit - Breaker Poles
5. Control of Lighting Circuit - Distribution System
6. Reversing Contactors
7. Plate Mounted Starters - Power & Control Circuit Diagram
8. Plate Mounted Starters - Star-Delta starter Circuit Diagram
9. Starters - Recommended Cabling for Reversal of Motor Rotation
10. Starters - Autotransformer Starters - Diagram
11. Protection of the Motor - Fuses / Breaker-Isolator
12. Enclosed Starters without Isolator
13. Enclosed Starters with Fusible Isolator
 
FAQ's (Frequantly Ask Questions)