B&B Electronics 485DSS manual Power Supply, RS-422 Wiring Diagram RS-485 and RS-422 Termination

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.

485DSS-0308 Manual 7

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