Rockwell Automation 8520 9/Series CNC Integration Maintenance Manual Documentation Set - Manual (Page 49)

Section 2A
Planning Your System Layout
2A-4
The components of the control, like all electronic devices, dissipate power
in the form of heat. The components and all modules in the control cabinet
must be continuously cooled to prevent overheating.
ATTENTION: If the internal temperature of the control cabinet
exceeds 55
° C (131 ° F), irreparable damage may result to the
control and its components within the enclosure and injury to
personnel.
Since solid state electronic equipment is more reliable at lower operating
temperatures, we recommend that the internal control cabinet temperature
be kept as cool as possible, without going below 0
° C (32 ° F).
Using Fans
Install fans inside the cabinet to keep the modules cool by circulating air
inside the enclosure as shown in Figure 2A.2. Do not blow the air directly
on the modules as this may cause accumulation of foreign matter on or
inside the module.
As fan driven air circulates inside the control enclosure, it absorbs some of
the heat dissipated by the control components. If this air circulation does
not guarantee sufficient thermal exchange through the cabinet walls, then
the air must be cooled before it comes in contact with the components
again.
Using Air Conditioners or Heat Exchangers
The approximate change in internal air temperature due to a heat
exchanger or air conditioner is a function of dissipated power, vertical
surface area, and air conditioner or heat exchanger rating. In calculating
the change in internal air temperature, be sure to use only the exposed
vertical surface areas of the enclosure; do not include the top or bottom of
the enclosure in the calculation.
Important: To help assure adequate internal air flow, do not mount any
obstructions within 0.6 meters of the intake and exhaust ports of fans, heat
exchangers or air conditioners.
2A.4
Maintaining Cabinet
Temperature