OTIS GEN II OI-6000, Руководство по эксплуатации

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PRODUCT SETTINGS AND CONFIGURATION
OI-6000-X-X-X-X-O OPS_GUIDE_REV 3.1 33
3.10 MODBUS ADDRESS SETTING
Modbus is the leading industrial open control protocol. Modbus is available in several different types, depending
upon the media over which it is transmitted. Like most communication protocols, Modbus uses a master/client type
behavior. The master sends a poll request for information to the client, the client decodes the request, and then
sends a response with the requested data back to the master.
A Modbus message includes a Modbus address, commonly referred to as a unit ID. The Modbus address is used
to identify the server address in RS-485 networks. Each server is assigned an address and listens for messages
which contain this number in the Modbus address field.
The OI-6000 uses the original Modbus RTU over the RS-485 link. RS-485 Modbus has 255 addresses, ranging from
1 to 255. Eight of the addresses are used for internal system settings, leaving addresses 1 to 247 available for your
device.
The RS-485 Modbus communication parameters used in Otis devices is 8 data bits, no parity, and 1 stop bit; these
parameters are fixed and cannot be changed. The floating point data values are presented with the least significant
bytes first.
When using Modbus over a RS-485 network, the communication parameters MUST be set correctly for all devices.
For multiple devices using Modbus, ensure that no two units are assigned the same address. A duplication of
addresses could cause errors in the transmission of data. Modbus addresses can be assigned sequentially or
another appropriate address scheme for the specific network setup.
The factory default setting on the OI-6000 for the Modbus address setting is 1.
1. Use the ADD and SUB buttons to increase and decrease the Modbus address number, respectively.
2. Press the MENU button to select the desired setting and to advance to the Modbus baud setting screen.