Rockwell Automation 1747-ACNR15 ControlNet Adapter Module User Manual - Manual (Page 132)

Publication 1747-UM003A-EN-P
B-40 Understanding Your SLC 500/1746 Control System
Example - Worksheet for Calculating Heat Dissipation
Procedure: Chassis 1 Chassis 2 Chassis 3
1. Calculate the heat dissipation for each chassis without the power supply
A. Write in the watts (calculated watts or total watts) dissipated by the processor, I/O and specialty
modules, and any peripheral devices attached to the processor. Then, for each chassis, add these
values together.
Chassis 1 Chassis 2 Chassis 3
Slot Catalog
Number Heat
Dissipation Catalog
Number Heat
Dissipation Catalog
Number Heat
Dissipation
0 L511 1.75 IA16 4.8
1 BAS 3.8 IA16 4.8
2 IA8 2.4 OW16 5.5
3 OV8 6.9 OW16 5.7
4
5
6
7
8
9
10
11
12
peripheral
DTAM 2.5
TOTAL 17.35 20.8
B. Place the heat dissipation for each chassis into the appropriate columns.
2. Calculate the heat dissipation for each power supply
A. Calculate the power supply loading for each chassis (write in the minimum
watts for each device, and then, for each chassis, add these values together.
Important: If you have a device connected to user power, multiply 24V by the
current used. Include user power in the total power supply loading
Chassis 1 Chassis 2 Chassis 3
Slot Catalog
Number Min. Heat
Dissipation Catalog
Number Min. Heat
Dissipation Catalog
Number Min. Heat
Dissipation
0 L511 1.75 IA16 0.425
1 BAS 3.750 IA16 0.425
2 IA8 0.250 OW16 5.17
3 OV8 0.675 OW16 5.17
4
5
6
7
8
9
10
11
12
user power
2.4
peripheral DTAM 2.5
TOTAL 8.925 13.59
B. Use the power supply loading for each chassis to determine the power supply dissipation. Place the
power supply dissipations into the appropriate columns.
3. Add the chassis dissipation to the power supply dissipation.
4. Add across the columns for the total heat dissipation of your SLC 500 controller.
TOTAL (Watts)
5. Convert to BTUs/hr.
Multiply the total heat dissipation of your SLC 500 controller by 3.414.
TOTAL (BtUs/hour)