F-5 thr – Rockwell Automation 1764-xxxx MICROLOGIX 1500 PROGRAMMABLE CONTROLLERS User Manual
Page 151

Publication 1764-UM001B-EN-P - April 2002
System Loading and Heat Dissipation F-5
System Using a 1769-PA2
To validate your system, the total 5V dc current and 24V dc current
consumed must be considered. The I/O modules must be distributed,
such that the current consumed from the left or right side of the
power supply never exceeds 2A at 5V dc and 1.0A at 24V dc. Use the
current graphs below to determine if the power supply loading in
your system is within the allowable range.
Figure F.1 1769-PA2 Current with +24V dc User Load = 0A
Table F.5 Bank 1 Power Supply Loading - Verify the Current Limits
Specification
Catalog Number
Calculated Current for System
24V dc User Output
Capacity
at 5V dc (mA)
at 24V dc (mA)
Values from SUBTOTAL2 (Table F.2):
(C)
(D)
MAXIMUM CURRENT LIMIT
1769-PA2
2000
800
250 mA
1769-PA4
4000
2000
n/a
1769-PB2
2000
800
1769-PB4
4000
2000
I/O Distribution - Distribute I/O modules
such that the current consumed from either
the left side or the right side of the power
supply never exceeds the following values:
1769-PA2
2000
800
250 mA
1769-PA4
2000
1000
n/a
1769-PB2
2000
800
1769-PB4
2000
1000
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0.0
0.5
1.0
1.5
2.0
+5
V
d
c
L
o
ad
(
A
m
p
s)
+24V dc Load (Amps)
Valid Operating Range