Agilent Technologies RS-232, Instruction Manual

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RS-232 and RS-485 Options for the senTorr Gauge Controller
DRA
FT
1-3
4. Set the DIP switches as per board type, as discussed below:
❑
RS–485
Refer to Table 1-2. If the senTorr is shipped with this option installed, the board is
configured as ordered.
A differential terminating resistance of 220 Ohms can be switched into the two-wire
pairs. The factory setting is unterminated (Table 1-3).
Table 1-2 RS–485 Selection
Switch Number RS–485
SW1-1 closed
SW1-2 open
SW1-7 closed
SW1-8 open
Table 1-3 RS–485 Terminating Resistance Selection
Switch Number
Number Terminating
Resistance
220 Ohm Terminating
Resistance
SW1-3 open closed
SW1-4 open closed