7ML19985MA01
SITRANS RD500 – OPERATING INSTRUCTIONS
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I/O Configur
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Port Settings
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Baud Rate: speed of data transmission in a system
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Data Bits: number of bits used to represent one character of data
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Stop Bits: number of bits used to mark the end of a unit of transmission
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Parity: an extra bit added to a byte or word to reveal errors in storage
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Port Mode: method of connection
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The Device field is used to enable or disable configured serial Modbus devices.
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The Name property allows a descriptive name to be applied to the Modbus enabled
sensor or device, e.g. HydroRanger 200 1.
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The Node property is used to define the Modbus address of the target slave device.
Nodes are addressable from 1 to 255.
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Slave Mapping supports communication to standard OPC server. Configured
instruments will be addressed to allow OPC servers to access their values through
the SITRANS RD500.
Configuring Modbus I/O
Once the Modbus devices have been added to the RD500 configuration, click Configure to
specify the registers to be monitored.
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The Address specifies the starting Modbus register address to be polled.
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The Elements field is used to specify the number of consecutive registers to be
polled, e.g. An Address of 400001 and an Elements property of 2 will result in the
RD500 collecting registers 400001 and 400002.
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The Type property defines the data type of the slave's data, including Bit, Word,
Long, and Real. Bits are packed into registers in groups of 16 bits (1 word).
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The Access property defines the registers as read-only, write-only, or read and
write.
