Endress+Hauser Proline Promass E 300, Руководство по эксплуатации

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Proline Promass E 300 Modbus RS485 System integration
Hauser 71
Code Name Description Application
16 Write multiple
registers Master writes a new value to
multiple Modbus registers of the
device.
A maximum of 120 consecutive
registers can be written with 1
telegram.

If the required device
parameters are not available
as a group, yet must
nevertheless be addressed
with a single telegram, use
Modbus data map →  72
Write multiple device parameters
Example:
• Mass flow unit
• Mass unit
23 Read/Write
multiple
registers Master reads and writes a
maximum of 118 Modbus registers
of the measuring device
simultaneously with 1 telegram.
Write access is executed
before
read access.
Write and read multiple device
parameters
Example:
• Read mass flow
• Reset totalizer
Broadcast messages are only allowed with function codes 06, 16 and 23.
9.3.2 Register information
For an overview of device parameters with their respective Modbus register
information, please refer to the "Modbus RS485 register information" section in the
"Description of device parameters" documentation →  198.
9.3.3 Response time
Response time of the measuring device to the request telegram of the Modbus master:
typically 3 to 5 ms
9.3.4 Data types
The measuring device supports the following data types:
FLOAT (floating point number IEEE 754)
Data length = 4 bytes (2 registers)
Byte 3 Byte 2 Byte 1 Byte 0
SEEEEEEE EMMMMMMM MMMMMMMM MMMMMMMM
S = sign, E = exponent, M = mantissa
INTEGER
Data length = 2 bytes (1 register)
Byte 1 Byte 0
Most significant byte (MSB) Least significant byte (LSB)
STRING
Data length = depends on the device parameter, e.g. presentation of a device parameter with a data length = 18
bytes (9 registers)
Byte 17 Byte 16 ... Byte 1 Byte 0
Most significant byte (MSB) ... Least significant byte (LSB)