LOYTEC L-STAT, Руководство пользователя

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L-STAT User Manual 20 LOYTEC
Version 1.0 LOYTEC electronics GmbH
3 Modbus
3.1 Introduction
The L-STAT operates as a Modbus slave in Modbus RTU mode. The default baudrate is set
to 57600, the default parity is set to ‘none’ and the default address is set to 1. The
communication with a Modbus master device will work with Modbus function code 0x03
(Read Holding Registers). Section 3.4 shows all available Modbus registers.
3.2 Modbus Network
Figure 5 illustrates a typical Modbus network setup with a linear bus topology used to
connect several slave devices to a master device. The transmission line has to be terminated
at both ends. At the master device this can be done by connecting an L-Term (LT-04)
device. Each L-STAT slave device is equipped with a built-in 120Ω termination resistor.
Set the termination switch to OFF except on the last device on the bus where the termination
switch must be turned ON.
Figure 5: Modbus Network