MODBUS RTU Protocol over RS485 Communications
The Modbus address is entered in variable N1 for the Analyzer.
Directions for Writing to this Variable
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Open the COMMAND CENTER and initiate communication with the Analyzer
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When the COMMAND CENTER communicates with the Analyzer, go to the VARIABLES
Page of the COMMAND CENTER
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Go to the User Input of the Variable Page. Click on the USER INPUT and
enter 'AMI' for the password when prompted. Then, return to the USER INPUT
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In the USER INPUT, enter the following to change the address of the Modbus:
A0WN1<Address>, where <Address> is 1-255
Note: By default, it is set to 17.
Using the Modbus RTU command, you can read the Analyzer's Modbus register(s):
(Note: There are a total of eight bytes to send)
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Byte 0 = Address (Modbus Bus Slave addressed to be entered into variable N1)
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Byte 1 = 3
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Byte 2 = 0
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Byte 3 = Register (Register equals the Starting Register for the Modbus read)
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Byte 4 = 0
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Byte 5 = Count (Count equals the Number of Registers to be read)
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Byte 6 = CRC Bytes
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Byte 7 = CRC Bytes
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