Maximum allowed current in function of the ambient temperature for installation method C
Ambient temperature
Cable section
30 °C
40 °C
45 °C
50 °C
55 °C
4 mm²
< 32 A
< 28 A
< 25 A
< 23 A
< 20 A
6 mm²
< 41 A
< 36 A
< 32 A
< 29 A
< 25 A
10 mm²
< 57 A
< 50 A
< 45 A
< 40 A
< 35 A
16 mm²
< 76 A
< 66 A
< 60 A
< 54 A
< 46 A
25 mm²
< 96 A
< 84 A
< 76 A
< 68 A
< 59 A
35 mm²
< 119 A
< 104 A
< 94 A
< 84 A
< 73 A
50 mm²
< 144 A
< 125 A
< 114 A
< 102 A
< 88 A
70 mm²
< 184 A
< 160 A
< 145 A
< 131 A
< 112 A
95 mm²
< 223 A
< 194 A
< 176 A
< 158 A
< 136 A
120 mm²
< 259 A
< 225 A
< 205 A
< 184 A
< 158 A
Installation method F according table B.52.1.
Single-core cables, touching in free air
Clearance to wall not less than one cable diameter
Maximum allowed current in function of the ambient temperature for installation method F
Ambient temperature
Cable section
30 °C
40 °C
45 °C
50 °C
55 °C
25 mm²
< 110 A
< 96 A
< 87 A
< 78 A
< 67 A
35 mm²
< 137 A
< 119 A
< 108 A
< 97 A
< 84 A
50 mm²
< 167 A
< 145 A
< 132 A
< 119 A
< 102 A
70 mm²
< 216 A
< 188 A
< 171 A
< 153 A
< 132 A
95 mm²
< 264 A
< 230 A
< 209 A
< 187 A
< 161 A
120 mm²
< 308 A
< 268 A
< 243 A
< 219 A
< 188 A
Calculation method for IEC:
• Single supply cables (3 PE - configuration (1)):
• Add 10 % to the total compressor current (I
tot
Pack or I
tot
FF from the tables)
• Install the prescribed fuse on each cable
• Parallel supply cable (2 x 3 PE - configuration (2)):
• Add 10 % to the total compressor current (I
tot
Pack or I
tot
FF from the tables) and divide by 2
• Multiply the ampacity of the cables with 0.8 (see table A.52.17 (52-E1))
• Install fuses of half the size of the recommended maximum fuse size on each cable.
• When using 2 x 3 PE as in (3):
• Add 10 % to the total compressor current (I
tot
Pack or I
tot
FF from the tables) and divide by √3
• Multiply the ampacity of the cables with 0.8 (see table A.52.17 (52-E1))
• Fuse size: the recommended maximum fuse size divided by √3 on each cable.
• Size of the PE cable:
• For supply cables up to 35 mm²: same size as supply cables
Instruction book
122
2920 7109 23
