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MODULE POWER REQUIREMENTS
SIZING THE MODULAR POWER SYSTEM
I-E96-508C
B - 5
output). For digital outputs, specify the current requirements
for the digital outputs in your system. Complete the calcula-
tion to determine the current requirements by filling in all five
rows as necessary then totaling the current requirements in
column four.
SIZING THE MODULAR POWER SYSTEM
The following text and equations explain how to calculate the
number of power supply modules needed for a particular
system.
Overall power requirements for 5 VDC, ±15 VDC, and 24 VDC
power are calculated by adding the individual module current
requirements. Refer to product specifications for current
requirements of modules not listed.
The combined 5 VDC and 24 VDC current output of any PDS
module should not exceed 102 watts (see Figure
). Use the
following procedure when sizing the modular power system to
assure that the PDS module operates within its power range.
For Systems with IEPDS01 or IEPDS02 Power Modules Only
Let:
A
= total 5 VDC current requirements for system cabinet
B
= total 24 VDC current requirements for associated I/O
C
= total +15 VDC current requirements for system
cabinet
D
= total -15 VDC current requirements for system cabinet
Table B-3. System Powered I/O Current Consumption
Type of Input/Output
Number of Inputs/
Outputs
Current Consumption
per Input/Output (mA)
Total Current
Consumption for
System Power I/O
Analog outputs
20
Analog inputs
20
Digital inputs
5
Digital outputs
See note
Total I/O current
consumption
NOTE: Use the typical current requirements of your particular digital outputs.