Rockwell Automation 1756-OF8I ControlLogix Eight-channel Isolated Analog I/O Modules - Manual (Page 199)

Rockwell Automation Publication 1756-UM540A-EN-P - May 2014 199
Appendix
B
Choose the Correct Power Supply
Power-sizing Chart You can determine the power that modules contained in a ControlLogix chassis
are consuming to maintain an adequate power supply.
An interactive spreadsheet is available that lets you enter a chassis configuration
and automatically calculates the total power supply consumption. The total
power supply consumption cannot exceed 75 W @ 60 °C (140 °F).
Refer to the configuration spreadsheet in Sizing the ControlLogix Power Supply,
Knowledgebase Technical Note ID 22753 .
The 5.1V DC and 24V DC currents are used together to calculate the maximum
backplane power dissipation. The following table lists the current draw of
each module.
Cat. No. Current Draw at 5.1V DC Current Draw at 24V DC
1756-IF8I 200 mA • Voltage/Non-sourcing Current mode: 150 mA
• Sourcing Current mode: 400 mA
1756-IRT8I 200 mA 150 mA
1756-OF8I 200 mA • Voltage or Current mode with 250
Ω
loads = 220 mA
• Current mode with 500
Ω
loads = 275 mA
• Current mode with 750
Ω
loads = 340 mA
• Current mode with 1000
Ω
loads = 385 mA