Design the clearances and creepage distances
in electrical equipment general
W
Technicalappendix
W.5
If the associated clearance air is
less than mm, the minimum slot
width can reduced 1/3 the
clearance.5
4 2.
For the design clearances and
creepage distances, application
of the regulations for insulation
coordination produces the following
interrelationships:
Clearances
Clearances are rated accordance
with the following factors:
• Anticipated overvoltage
rated impulse withstand voltage
• Used overvoltage protection
precaution
• Measures prevent pollution
pollution severity
Creepage distances
Creepage distances are rated in
accordance with the following factors:
• Planned rated voltage
• Insulation materials used
insulation group
• Measures prevent pollution
pollution severity
Slots are taken into account when
measuring creepage distances their
minimum width dimensioned
according the following table:
Pollution severity min.25
2 1
3 1. width
X [mm]
1 0.16 1282250000 2012/2013
.
The design data resulting from these
provisions applicable specified
in this catalogue for each product.Electrical data
Since April 1997 the sizing of
clearances and creepage distances
has been covered IEC 60664-1
“Insulation coordination for electrical
equipment low-voltage systems”
