Rockwell Automation 1770-HT8 SMART TRANSMITTER - Manual (Page 47)

Installing the Smart Transmitter Interface
Products
Chapter 2
2-22
4. Turn the power supply on.
Important: The loop power and ground common wires are only needed if
the HART field devices connected to the Terminal Blocks draw power
from the 4-20 mA current loop instead of from their own individual power
supplies. The earth ground wire is needed, whether or not loop power is
being supplied.
Figure 2.19
Connecting an External Power Supply to a Terminal Block for Loop Power to HART
Field Devices
90028
LOOP POWER
EARTH
GROUND
COMMON
Terminal Block
+ -
Loop Power
The RIO connector is a 3 position Phoenix COMBICON connector located
at the left end of the unit, just to the right of the DB-25 connector, at the
top edge of the board (see Figure 2.20). Attach the matching plug (supplied
with the Communications Controller) to the RIO cable. Insert the plug into
the connector to make the RIO connection.
Connecting the
Communications Controller to
the RIO Host