Connecting the STM23/24 Communications

The STM17, STM23 and STM24 are available with two types of serial communication: RS-232 (-xAx) or RS-422/485 (-xRx). Each type requires a different hardware connection for interface to a PC or other host system. The RS-232 version comes with a cable that will provide the interface to an RS-232 port through a DB9 style connector. The RS-422/485 version requires the user to provide both the cabling and the RS-422/485 interface. The CANopen (-C) version also includes an RS-232 port for configuration. Below are descriptions of how to interface the STM to a PC. For RS-422/485 wiring, please read the appropriate hardware manual.

Connecting to a PC Using RS-232
• Locate your computer within 8 feet of the Drive+Motor.
• Your drive was shipped with a communication cable. Plug the large end into the serial port of your PC and the small end into the RS-232 jack (RJ-11 connector) on your drive. Secure the cable to the PC with the screws on the sides.
Never connect a drive to a telephone circuit. It uses the same connectors and cords as telephones and modems, but the voltages are not compatible.
NOTE: If the PC does not have an RS-232 serial port, a USB Serial Converter will be needed. For more information, please read Connecting to an STM24 Using USB in the Hardware Manual.

RS-232 Connector for S, SF, Q and QF Models (RJ11 connector)

RS-232 Connector for C Models

The RS-232 circuitry does not have any extra electrical "hardening" and care should be taken when connecting to the RS-232 port as hot plugging could result in circuit failure. If this is a concern the RS-422/485 version should be used.
Do not plug or unplug the RS-232 connection while power is applied to the drive. This is known as "hot plugging" and should be avoided.