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Xylem Expert 7060_7070_Modbus User Manual

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Communication protocol Serie30

Page 26/37

5.10

Function 74 : Read value of a channel (integer)

Request:

DevAddr 74

CH

CRC16_H CRC16_L

Response:

DevAddr 74

B3

B2

B1

B0

STAT

CRC16_H CRC16_L

Exception errors:

2

If CH > 5

3

If message length is incorrect

4

If a channel is in overflow/underflow/inactive state or the data is invalid

32

If device has not yet been initialised

Note:

Only in devices of Class.Group = 5.20.

Same as function 73, but values in 4-byte integer (long) B0 .. B3, where B3 is MSByte. The resolution is reduced to 0.1mbar.

Unit: CH0, P1 and P2: in Pascal (1Pa = 10

-5

bar).

T, TOB1 and TOB2: in 0.01°C

Status-Byte (STAT): See function 73.

For details in error-handling see chapter Error handling and recognition!