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CHAPTER 3: Installation and Operation
Figure 3-2. DIP-switch location.
The factory setting should work for most installations. S/T interface links that have
unusual characteristics may experience improved performance by putting resistors
in or out of the circuit. The units on the opposite end of the S/T line also have
terminating resistors that you must consider. As a general rule, the units at either
end have the resistance in while add-on nodes have the resistance out. Table 3-1
shows the switch settings.
Table 3-1. DIP-switch functions
DIP-Switch
Transmit Resistor
Receive Resistor
Position
OFF
ON*
S1-1
100 ohms out
100 ohms in
S1-4
OFF
ON*
100 100
ohms out
ohms in
*Default setting.
NOTES
ON=Down and OFF=up. Set both resistors the same, either both ON or
both OFF.
S1-2 and S1-3 are not used.