From these given initial data also the k
SF
correction factor can be calculated by multiplying them
together (k factor related information in red color):
so the settings would be then In = 680 A, Tmax = 90
̊
C, Tamb = 15
̊
C, Tref = 15
̊
C and k
SF
= 0.81
Figure. 5.4.21. - 104. Thermal image response with nominal currents and ne tuned k
SF
correction factor.
Now when trying to load the cable with the given nominal current can be seen that the actual cable
current carrying capacity is much lower than in presumption conditions. Normal loading current can
now get the cable too warm and endanger its withstandability. If in this case the k
SF
factor would not
been set the thermal image would show about 68
̊
C temperature when it in reality would be 96
̊
C.
AQ-F255
Instruction manual
Version: 2.00
175
© Arcteq Relays Ltd