
13
CHAPTER 3: Installation
Table 1. DCE Jumper Settings (continued)
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.