ST21 comprises a PC program, providing the human interface and a transmitter built-in board, the T210. The T210 is a Modbus to HART protocol converter for transforming a Modbus RTU instrument to communicate on a HART network.
ST21 is a tool suited for learning the HART protocol and to provide guidance for an instrument vendor that needs help to specify HART functionality for its own products.
The Starter kit Master software is the SW02, running under any version of Windows. The kit may contain one, five or ten transmitter boards. See below for the different options available. The software will instruct the user in how to use the HART protocol and commands. The user learns about the functionality provided by the HART Universal and Common Practice commands through extensive “help” menus.
The Tool kit will give the user ideas on how the functionality of a HART device may be added by using Device Specific Commands. These allow a vendor to fully exploit the HART protocol and thus get an idea of implementation opportunities.
The T210 is a built-in board. It supports the Modbus protocol for communication with the instrument. The Modbus communication needs to be configured to allow T210 to fetch the Primary Variable and the Device Status from the correct registers within the instrument and make them available on the HART interface.
T210 supports either RS485, RS232 or pure CMOS circuitry for connecting to the Modbus interface.
ST21 requires a HART modem which may be ordered as an option to the ST21.
ST21 is a useful tool for the device developer and for later use in connection with factory configuration of the developed device.