Atlas Copco GA 110 VSD+ Instruction Book page 70

Cable sizing according UL
The table below indicates the current carrying capacities of cables for commonly used installation
methods, according to standard UL 508A. Ampacities of insulated conductors, copper 75°C.
AWG or kcmil
10
8
6
4
3
2
1
1/0
2/0
3/0
4/0
250
300
350
400
500
Note: The above table has been prepared for user convenience. Only the latest editions of the UL
standard and its amendment(s) are to be considered as the official documents.
Cable calculation method for UL
Calculation method according UL 508A
• Single supply cables (3 phases + PE)::
• Add 25 % to the total package current (Package current from the technical data
sheets).
• Install fuses on each supply cable which are smaller than or equal to the Max. fuse
values from the technical data sheets or instruction manual.
• Connection between contactors must be made by means of copper bars.
• Parallel supply cables (2 x (3 phases + PE)):
• Add 25% to the total package current (Package current from the technical data sheets)
and divide by 2.
• Install fuses which are smaller than or equal to the Max. fuse values from the technical
data sheets or instruction manual.
• Size of the PE cable
• Use the maximum allowed ampacity of the selected supply cables and compare with
the value in the table below according to UL508A.
Ampacity
< 90 A
< 125 A
< 150 A
68
Ampacity
< 30 A
< 50 A
< 65 A
< 85 A
< 100 A
< 115 A
< 130 A
< 150 A
< 175 A
< 200 A
< 230 A
< 255 A
< 285 A
< 310 A
< 335 A
< 380 A
Size of PE
8 AWG
6 AWG
6 AWG
Instruction book
9829 3178 63