QuickServer Start-Up Guide
Page 30 of 46
Appendix A Useful Features
Appendix A.1. RS-422 Connection R2 Port (only available on the FS-QS-123X models)
RS-422 is a full duplex multi-drop multi-master differential bus. It can be wired to conform to a RS-485
network when less wiring/cabling is used (due to being less expensive to install), but then it becomes a
half-duplex multi-drop multi-master differential bus. RS-422 is used for dedicated peer to peer high speed
communication when low bus latency is required i.e. very few devices on the bus. Its usage is very
specific to client installations/requirements.
NOTE:
The RS-232 looks similar to the RS-485 but does not have the blue jumper. The blue jumper is
used to enable the termination resistor for the RX signals (120 ohms), while the red jumpers are
used to enable the bias resistors for RX signals (510 ohms). In the case of Rockwell/Tetrapak, all
jumpers are always required to be in default position i.e. not enabled. For other clients, the bias
resistors should always be in the on state.
The part number on the back of the box will identify the port.
Figure 22: RS-422 Unit