Xylem Expert 7060_7070_Modbus - Manual (Page 21)

Communication protocol Serie30
Page 27/37
5.11 Function 95 : Commands for setting the zero point
Requests:
Request a:
DevAddr 95 CMD CRC16_H CRC16_L
Request b with setpoint:
DevAddr 95 CMD B3 B2 B1 B0 CRC16_H CRC16_L
where B3:B0: Floating-piont number IEEE754 format (4-byte B0 ... B3) for the setpoint.
Response:
DevAddr 95 0 CRC16_H CRC16_L
Exception errors:
1 If in Power-up mode
2 If CMD invalid
3 If message length incorrect
32 If device is not yet initialised
Note:
The following actions can be carried out with this function:
CMD Meaning
0 Set zero point of P1
1 Reset zero point of P1 to standard value
2 Set zero point of P2
3 Reset zero point of P2 to standard value
4 Update DAC scaling ( Class.Group = 5.1 only)
5 --
6 Set zero point of CH0
7 Reset zero point of CH0 to standard value
CMD 0, 2, 6:
Zero point values for pressure channels P1, P2 and the calculated channel CH0. These values can also be read via function 30
and written via function 31.
Request a: The zero point is calculated such that the current measured value = 0.0.
Request b: The zero point is calculated such that the current measured value equals the setpoint (B3:B0).
CMD=6, CMD=7 and request b are only available in devices of Class.Group 5.20.
CMD 1, 3, 7: Reset zero point to factory setting
The zero point values are reset to 0.
Devices with zeroing button:
The devices may optionally possess a zeroing button. The zero point is then set as follows by means of this button:
If only P1 is active, the zero point value of P1 is calculated such that P1 = 0.
If channels P1 and P2 are active, the zero point value of P2 is calculated such that P2 = P1.