Power supply – B&B Electronics 485DSS User Manual
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485DSS-0308 Manual
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B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104
B&B Electronics – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 91 792444 – Fax +353 91 792445
Figure 4. RS-422 Wiring Diagram
RS-485 and RS-422 Termination
A jumper labeled “TERM” provides termination for the RS-
485/422 receiver. The termination resistor is a 120-ohm resistor
placed between the RD (A) and RD (B) lines. To use this
termination, place the jumper in the "IN" position. Refer to Figure 2
for the location of this jumper. If there is no need for termination,
place the jumper in the "OUT" position. For more discussion of
termination refer to B&B Electronics’ free RS-422/485 Application
Note.
Power Supply
The 485DSS requires an unregulated DC power source that will
supply +12 volts at 100 milliamps. Connect the positive side of the
power source to the +12VDC terminal block and the common side of
the power source to the GND terminal block. Refer to Figure 2 for
the location of the terminal blocks and the polarity. B&B Electronics'
power supply Model 485PS2 is available for the 485DSS.