Rockwell Automation 1770-HT8 SMART TRANSMITTER - Manual (Page 31)

Installing the Smart Transmitter Interface
Products
Chapter 2
2-6
Star Connection
For star connection the cables to each Terminal Block lead to the connector
on the Communications Controller directly. If you are using a star
arrangement, the connector at the Communications Controller will have as
many sets of wires leading into it as there are Terminal Blocks. The
connector at each Terminal Block will have only one set of wires, leading
directly back to the Communications Controller.
Figure 2.4
Example 2: Star Connection
90030
1770ĆHT8
1770ĆHT8
1770ĆHT8
1770ĆHT8
a
b
c
d
+ -
+ -
+ -
+ -
+ -
Example 2 assumes that the modules (HT1, and four HT8’s) are installed
in separate cabinets. The table below gives one example of possible cable
lengths.
Cable Size Cable a Cable b Cable c Cable d
Belden #85168 250 ft 250 ft 250 ft 250 ft