17
CHAPTER 3: Installation
Table 1 (continued). DCE Jumper Settings.
Function
Jumper Requirements
7. RS-485 interface terminated
or unterminated
• Terminated
S2 in TERM position
• Unterminated
S2 in UNTERM position
8. Normal or loopback operation
• Normal mode
S1 in Normal position
• Loopback mode
S1 in Loopback position
9. RS-485 Interface Line Biased (Fail-
S3 Off
No line bias
Safe), Receive
S3 On
Line biased
NOTE
If line bias is on, the RS-485 CD will ALWAYS be on.
