KROHNE MFC 300 Modbus - Manual (Page 17)

MODBUS PROTOCOL
6
17
MFC 300
www.krohne.com 11/2009 - 4000744801 - AD Modbus MFC 300 R01 en
6.10 Calibration procedures
6.10.1 Zero Calibration
1 User reduces the actual flow through the meter to User reduces the actual flow through the meter to User reduces the actual flow through the meter to User reduces the actual flow through the meter to
zero
zero zero zero
2 Start zero calibration: Start zero calibration: Start zero calibration: Start zero calibration:
Set single coil 2000 to 1 (Modbus Fct. 0x05)
3 Check status of calibration Check status of calibration Check status of calibration Check status of calibration
Read single coil 2000 (Modbus Fct. 0x01)
3a [2000 == 1: calibration running]
3b [2000 == 0: calibration complete]
4 Read Calibration Value Read Calibration Value Read Calibration Value Read Calibration Value
Read Input Register 20000 type float
(Modbus Fct. 0x04)
5 User checks the calibration value: User checks the calibration value: User checks the calibration value: User checks the calibration value:
-10...+10: acceptable result
5a Not ok
5b ok
6 User tries to improve the calibration situation User tries to improve the calibration situation User tries to improve the calibration situation User tries to improve the calibration situation
6a Improvement done
6b Improvement not possible
-Break-
7 Write the calibration value Write the calibration value Write the calibration value Write the calibration value
Write Holding Register 43000 type float
(Modbus Fct. 0x10)
8 Read Calibration Temperature Read Calibration Temperature Read Calibration Temperature Read Calibration Temperature
Read Input Register 20002 type float (Modbus
Fct. 0x04)
9 Write Calibration Temperature Write Calibration Temperature Write Calibration Temperature Write Calibration Temperature
Write Holding Register 43002 type float (Modbus
Fct. 0x10)
10 Activate new values Activate new values Activate new values Activate new values
Set single coil 1001 to 1 (Modbus Fct. 0x05)
10a This results in a warm start of the device.
Will take maximum 5s.
.book Page 17 Tuesday, November 24, 2009 1:48 PM