KROHNE IFC 300 Converter Modbus EN - Manual (Page 18)

6
MODBUS PROTOCOL
18
IFC 300
www.krohne.com 07/2010 - 4000410703 - AD Modbus IFC 300 R03 en
6.10 Calibration procedures
6.10.1 Zero Flow 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:
-0.01...+0.01: good results
-0.1...+0.1: acceptable result for difficult
application
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 43024 type float
(Modbus Fct. 0x10)
8 Activate new values Activate new values Activate new values Activate new values
Set single coil 1001 to 1 (Modbus Fct. 0x05)
8a This results in a warm start of the device.
Will take maximum 5s.
.book Page 18 Friday, July 9, 2010 10:31 AM