Rockwell Automation 1746-NO8V SLC 500 8-Point Analog Output Module - Manual (Page 6)

6 SLC 500 8-Point Analog Output Module
Publication 1746-IN026A-EN-P - July 2003
Determining Power Requirements
The module receives its power through the SLC 500 chassis backplane from the
+5V dc/+24V dc chassis power supply. The +5V dc backplane supply powers the
SLC circuitry, and the +24V dc backplane supply powers the module analog
circuitry. The maximum current drawn by the module is shown in the table below.
Add the values shown in the table above to the requirements of all other modules
in the SLC chassis to prevent overloading the chassis power supply. Refer to your
controller’s User Manual for power supply loading calculations and worksheets.
Using an External 24V dc Power Supply (optional)
The jumper, J4, is located in the bottom right corner of the module’s circuit board
next to the power supply.
Table 3 1746-NO8 Backplane Current Consumption
Specification 1746-NO8I 1746-NO8V
Backplane Current Consumption (maximum) 120 mA at 5V dc
250 mA at 24V dc 120 mA at 5V dc
160 mA at 24V dc
Backplane Current Consumption (maximum)
when Using External 24V dc Power Supply
(1)
(1) The 1746-NO8I and 1746-NO8V output modules can use an external 24V dc power supply to reduce backplane loading. To
use an external 24V dc power supply, you must set your module’s jumper J4 as indicated in the following section. To comply
with the U.L. regulation, the external power supply must be rated N.E.C. Class 2. Do not use the 24V dc user power terminal
on the chassis power supply to power the analog output module.
NOTE: The external 24V dc power supply terminal block ground connection (DC COM) is connected to the SLC power supply
ground.
120 mA at 5V dc
0 mA at 24V dc 120 mA at 5V dc
0 mA at 24V dc
RACK
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3
J4 jumper location