Rockwell Automation 1746-HSRV SLC Servo Control Module User Manual - Manual (Page 25)

Publication 1746-6.1.2 - July 2000
2-2 Selecting Power Supplies, Encoders, and Drives
Example of Calculations for Backplane Current Requirements
In this example, the system includes:
•
One seven-slot modular rack
•
One 1747-L543 CPU module
•
One 1746-IB8 DC input module with eight inputs @ +24V
•
One 1746-OV8 DC output module with eight outputs @ +24V
•
An SLC Servo Module system that contains:
•
SLC Servo Modules
•
Termination panels
•
Allen-Bradley 845H encoders
•
Fast inputs
•
Fast outputs
Use the table below to find the current requirements of the devices
using backplane power. Those devices that are not included in the
backplane calculations are included in the example’s user-side
calculations.
If optional processor is used:
Device +5V +24V
1746-L543 processor 1A .200A
SLC Servo Module .300A 0
1746-IB8 .040A 0
1746-OV8 .125A 0
Total = 1.465A Total = .200A
Device +5V +24V
1747-L532 processor .500A .175A
SLC Servo Module .300A 0
1746-IB8 .040A 0
1746-OV8 .125A 0
Total = .965A Total = .175A