Hamilton Electronics EPHUM011 - Manual (Page 41)

pH ARC Sensors Modbus RTU Programmer ’ s Manual (EPHUM011)
624300/01 page 41 / 67
The different functionalities of product calibration (CP6) are accessible through the following sensor
commands:
 Initial measurement
 Assignment
 Cancel
 Restore standard calibration
 Restore product calibration
All commands are executed by writing a command value to the register 5340 except for assignment
where the calibration value is written to register 5322 (see below).
Definition of the commands for product calibration
The commands for register 5340 are defined as follows:
Code Hex Definition of commands
0x01 Perform initial measurement
0x02 Cancel an active product calibration
0x03 Restore a standard calibration from an active product calibration
0x04 Restore a product calibration from an active standard calibration
Figure 2.7.3.2.2: Definition of the commands related to the product calibration
Start
register Number of
registers Reg1 / Reg2 Modbus
function code Read
access Write
access
5340 2 Code as defined in Figure 2.7.3.2.2 3, 4, 16 A/S A/S
Figure 2.7.3.2.3: Definition of register 5340
2.7.3.2.1 Product calibration: Initial measurement
Upon process sample collection for laboratory analysis the command for initial measurement is sent to
the sensor.
This is achieved by writing the command 0x01 to register 5340 which performs the initial measurement
and stores the corresponding measurement values in the sensor.
Command: CP6: Initial measurement Modbus address: 5340 Length: 2 Type: 16
Write
Parameter: Command
Format: Hex
Value: 0x01
Figure 2.7.3.2.1.1: Example to start the product calibration procedure. Writing the command code 0x01
(initial measurement) to the CP6 command register 5340.
After successful initial measurement the corresponding calibration status (register 5318, figure
2.7.4.2.1) is
“ CP6 initial measurement ”(0x08000000) (see figure 2.7.4.1.1).
The sensor continues measuring using the prior standard calibration.