Emerson Micro Motion 9739 MVD, Руководство по конфигурации и использованию

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Integrate the meter with the control system
The primary reason to disable Modbus ASCII support is to allow you to use the full range of
Modbus addresses that are available for your Modbus connections (1 to 127). If Modbus ASCII
support is enabled, you are limited to using the following Modbus addresses: 1–15, 32–47,
64–79, and 96–110.
2. Set Modbus Address to a value between 1 and 127, excluding 111. (111 is reserved for the service
port.)
3. Set Floating-Point Byte Order to match the byte order used by your Modbus host.
Code Byte order
0 1 – 2 3 – 4
1 3 – 4 1 – 2
2 2
–
1 4
–
3
3 4 – 3 2 – 1
The bit structure of bytes 1, 2, 3, and 4 is shown in Table 7-14 .
Table 7-14 Bit structure of floating-point bytes
Byte Bits Definition
1 SEEEEEEE S=Sign
E=Exponent
2 EMMMMMMM E=Exponent
M=Mantissa
3 MMMMMMMM M=Mantissa
4 MMMMMMMM M=Mantissa
4. (Optional) Set Additional Communications Response Delay in “delay units.”
A delay unit is 2/3 of the time required to transmit one character, as calculated for the serial port
currently in use and the character transmission parameters. Valid values range from 1 to 255.
Additional Communications Response Delay is used to synchronize Modbus communications with hosts
that operate at a slower speed than the transmitter. The value specified here will be added to each
response the transmitter sends to the host.
Tip
Do not set Additional Communications Response Delay unless required by your Modbus host.
7.6.4 Configure
Digital Communications Fault Action
Display Not available
ProLink II ProLink→Configuration→Device→Digital Comm Settings→Digital Comm Fault Setting
Field Communicator Configure→Alert Setup→Inputs/Outputs Fault Actions→Digital Communications
Digital Communications Fault Action specifies the values that will be reported via digital communications if the
transmitter encounters an internal fault condition.
144 Micro Motion 9739 MVD Transmitters