Rockwell Automation Allen-Bradley 2094-BM01-S - Page 28

28 Rockwell Automation Publication 2094-UM001D-EN-P - May 2010
Chapter 2 Planning the Kinetix 6000 Drive System Installation
Table 7 - ControlLogix System Heat Dissipation Example
Figure 5 - ControlLogix Real Power
For backplane power loading requirements of other ControlLogix power
supplies, refer to the ControlLogix Selection Guide, publication 1756-SG001
.
In this example, the amount of power dissipated inside the cabinet is the sum of
the Bulletin 2094 system value (578 W) and the ControlLogix system value
(34 W) for a total of 612 W.
With no active method of heat dissipation (such as fans or air conditioning)
either of these approximate equations can be used.
Enclosure
Component
Description
Backplane Power
Load
(1)
watts
Heat Dissipation
(1)
watts
1756-M08SE 8-axis SERCOS interface module 3.2 0
1756-L5563 L63 ControlLogix processor 4.5 0
1756-IB16D 16 -point input module 0.84 5.8
1756-OB16D 16 -point output module 4.64 3.3
1756-ENxTx EtherNet/IP communication module 4.0 0
Backplane total
17.18
(2)
N/A
1756-PB72 24V DC ControlLogix power supply N/A
25
(2)
1756-A7 7-slot mounting chassis N/A N/A
Total ControlLogix system wattage 34.1
(1) For ControlLogix module specifications, refer to the ControlLogix Selection Guide, publication 1756-SG001.
(2) Real power heat dissipation is determined by applying the backplane power load (17.18W) to the graph below.
75
60
45
30
15
0
0 20 40 60 80 100
Backplane
Power Load
(watts)
Real Power (watts)
1756-P B72
1756-P B75
DC
Metric Standard English
Where T is temperature difference between
inside air and outside ambient (°C), Q is heat
generated in enclosure (Watts), and A is
enclosure surface area (m
2
). The exterior surface
of all six sides of an enclosure is calculated as
Where T is temperature difference between
inside air and outside ambient (°F), Q is heat
generated in enclosure (Watts), and A is
enclosure surface area (ft²). The exterior surface
of all six sides of an enclosure is calculated as
A = 2dw + 2dh + 2wh A = (2dw + 2dh + 2wh) / 144
Where d (depth), w (width), and h (height) are in
meters.
Where d (depth), w (width), and h (height) are in
inches.
A =
0.38Q
1.8T - 1.1
A =
4.08Q
T - 1.1