Ultra-cut 300, Line termination, Rs 485 with multiple ccms – Tweco 300 Ultra-Cut(March 2013) User Manual
Page 145: Rs 422 4 wire half duplex, Ccm address

Manual 0-5134
A-13
APPENDIX
ULTRA-CUT 300
Recommend using the 4 wire when possible as it is easier to troubleshoot if there is a problem. Note that CCM Tx+
connects to CNC Rx+ and CCM TX- connects to CNC RX- for 4 wire half duplex. If using 2 wire RS 485 connect CCM
Tx+ (also called D+ or Data +) to CNC Tx+ and CCM Tx- (also called D- or Data- ) to CNC Tx-. The Rx wires are not
used for 2 wire.
Line termination:
RS 485 and RS 422 are both “multi-drop protocols, that is there can be multiple devices on the same line. We do not
currently support more than one CCM. Until we do line termination should always be ON.
For RS 485 it is recommended that the communication lines be terminated at each end with the line’s characteristic
impedance. For RS 422 it is recommended the line be terminated at the receiver end.
The CCM has a line termination switch SW14 whose default position is ON. For CCMs that are not at the end of the
line (like CCM #1 & #2 below) switch off SW14.
RS 485 with multiple CCMs:
120
120
Signal GND also required but not shown.
SW14 OFF
SW14 OFF
SW14 ON
TSC 3000 (HMI)
or CNC using
2 wire RS 485
CCM #1
CCM #2
CCM # (last in line)
Data+
Data-
Art # A-09483
RS 422 4 wire half duplex:
Tx-
Tx+
Rx-
Rx+
Tx
Tx
Tx
Rx
Rx
Rx
Signal GND also required but not shown.
120
120
SW14 OFF
SW14 ON
CCM #1
CNC using
RS 422 half
duplex
SW14 OFF
CCM # (last in line)
CCM #2
Art # A-09484_AB
CCM Address:
When more than one device is used in parallel on a serial communication line each has to have a unique address. The
CCM has a switch SW10 to set the address of each CCM. The “0” factory setting is correct for system with one
plasma (one CCM). We do not currently support CCMs in parallel. When that becomes available details for setting
other addresses will be included in an updated manual explaining installation and set up of parallel systems.