B&B Electronics manual Wire RS-422 or RS-485 Connections

Models: RS-422

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4-Wire RS-422 or RS-485 Connections

Figure 6.2

Note: With RS-422 Devices, connect only one device to computer..

Connect the TD(B) pin #2 on the computer to RD(B) on the device.

Connect the TD(A) pin #3 on the computer to RD(A) on the device.

Connect the RD(B) pin #9 on the computer to TD(B) on the device.

Connect the RD(A) pin #1 on the computer to TD(A) on the device.

Connect the Signal Ground pin #5 to Signal Ground on the device.

In a 4-wire RS-485 system, each receive line connects to the same receive terminal on all slaves, and each transmit line connects to the same transmit terminal on all slaves. The master to the first slave is connected as above.

In a multi-slave RS-422 connection, TD(B) and TD(A) connect to RD(B) and RD(A) on all the slaves. If the slaves have Transmit connections, only one device can be connected back to the master. See Fig. 6.3 on next page.

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Chapter 6

Documentation Number 3PCIO1-0903 Manual

B&B Electronics Mfg Co – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104 B&B Electronics Ltd – Westlink Comm. Pk. – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445

Page 49
Image 49
B&B Electronics manual Wire RS-422 or RS-485 Connections