- 6 -
Special environmental conditions

When using the VCB in special environments, check the points in Table 1 below.

Table 1 Points to Check When Using the Circuit Breaker in Special Environments
Special
environmental
condition
Practical example Check points
Contamination * Large amounts of dust.
* Salt corrosion (locations near the
seashore or where winds containing
salts blow)
* Reduce the size of the ventilation duct
* Make sure the wind does not blow
directly at the location where the
ventilation duct is installed
* Install a filter
High humidity * Places subject to frequent and/or
strong rainstorms or snowstorms
* When there is a cooling tower or
other large water source nearby
* Where there is condensation (which
forms when the humidity in the
cubicle drops dramatically)
* Use a cubicle construction that will
prevent condensation from forming
* Use a cubicle construction that will
prevent the wind from blowing directly
into the cubicle
* Install a space heater
Corrosive gases * When corrosive gases are produced
at plants handling raw materials, at
water treatment plants, in hot
springs regions etc. (hydrogen
chloride, sulfurous acid, nitrogen
oxide, ammonia, chlorine, ozone
etc. or other gases)
* Use a cubicle construction that
enables the cubicle to be blocked off
from the outside air to the greatest
extent possible
* Install a filter