Rockwell Automation 1747-L40 SLC 500 Fixed Hardware Style - Manual (Page 119)

Appendix A
Setting Up the DH-485 Network
A–14
Powering the Link Coupler
In normal operation with the programmable controller connected to the link
coupler, the processor powers both the link coupler and peripheral device
(DTAM, PIC, HHT) — if connected — through the C11 cable.
If you do not connect the processor to the link coupler, then use a 24 VDC
power supply to power the link coupler and peripheral device. The
1747–AIC requires 85mA at 24 VDC. With a peripheral device connected,
the total current required is 190mA at 24 VDC.
If both the processor and external power are connected to the link coupler,
only the external source is used.
Important: Always connect the CHS GND (chassis ground) terminal to the
nearest earth ground. This connection must be made whether or
not an external 24 VDC supply is used.
Below are three options for externally powering the 1747–AIC:
•
If the link coupler is to be installed in an office environment, you can use
the wall mount power supply (1747–NP1) or global desktop power supply
(1747–NP2). The link coupler would be powered through either the
1747–C10 cable or by hardwiring from the supply to the screw terminals
on the link coupler.
•
If you use the AC chassis power supplies (1746–P1 or 1746–P2), you can
use the 24 VDC user power supply (200mA maximum) built into the
power supply. The link coupler would be powered through a hard–wired
connection from the screw terminals on the power supply to the screw
terminals on bottom of the link coupler.
•
You can use an external DC power supply with the following
specifications:
– operating voltage: 24 VDC + 25%
– output current: 190mA
– rated NEC
The link coupler would be powered through a hard–wired connection
from the external supply to the screw terminals on the bottom of the link
coupler.
!
ATTENTION: If you use an external power supply, it must be
24 VDC. Permanent damage will result if miswired with the
wrong power source.