199 / 210
199
A switchboard is designed for operation under normal ambient conditions.
Most devices do not operation correctly outside a temperature range of -10 and
+70 °C.
It is therefore important to maintain the switchboard internal temperature within this
temperature range by:
b
b
correctly sizing the switchboard during design
b
b
correcting the temperature using suitable means.
Management of the internal temperature
Cooling
There are a number of way to dissipate heat from the switchboard.
The drawings below present the various means.
Convection
Forced-air ventilation
Dd383633.eps
Dd383634.eps
Dd383635.eps
IP > 31
IP
y
31
IP
y
54
Ensured naturally in Prisma enclosures.
Using fans, it significantly
increases the thermal
capacity of an enclosure.
Forced-air ventilation
with air-air exchanger
Forced convection and
cooling
Dd383637.eps
?
Dd383638.eps
IP > 31
IP > 31
On special request.
For these extreme cases, many installers prefer to set up the switchboards with
other electrotechnical and electronic devices in air-conditioned electrical rooms.
Heating
The means employed to raise the internal temperature in a switchboard is a
resistorbased heater, used to:
b
b
avoid condensation by limiting variations in temperature
b
b
ensure that the switchboard does not freeze.
Additional information
Thermal characteristics
Thermalmanagement
of switchboards
General