Hamilton Electronics EPHUM011 User Manual
Page 44

pH ARC Sensors Modbus RTU Programmer
’
s Manual (EPHUM011)
624300/01
page 44 / 67
2.7.4 Reading the Calibration Status
2.7.4.1
Reading the Calibration Status of CP1 and CP2
A standard calibration is not always successful. In order to analyze what has gone wrong, two different
calibration status registers can be read:
Register 5158 for CP1
Register 5190 for CP2
Note
Registers 5158 and 5190 contain the same information!
Bit #
Hex value
Definition
0 (LSB)
0x00000001
CP1: difference between CP1 and CP2 < pH 1.0
1
0x00000002
CP1: no matching calibration standard
2
0x00000004
CP1: actual temperature reading is too low
3
0x00000008
CP1: actual temperature reading is too high
4
0x00000010
CP1: temperature reading during calibration is not stable
5
0x00000020
CP1: offset a pH 7 is too low or slope is too low
6
0x00000040
CP1: offset a pH 7 is too high or slope is too high
7
0x00000080
CP1: pH reading during calibration is not stable
8
0x00000100
CP2: difference between CP2 and CP1 < pH 1.0
9
0x00000200
CP2: no matching calibration standard
10
0x00000400
CP2: actual temperature reading is too low
11
0x00000800
CP2: actual temperature reading is too high
12
0x00001000
CP2: temperature reading during calibration is not stable
13
0x00002000
CP2: offset a pH 7 is too low or slope is too low
14
0x00004000
CP2: offset a pH 7 is too high or slope is too high
15
0x00008000
CP2: pH reading during calibration is not stable
…
not available
24
0x01000000
CP6: out of calibration range
25
0x02000000
CP6: out of range
26
0x04000000
CP6: active
27
0x08000000
CP6: initial measurement
28
0x10000000
CP6: assigned
not available
30
0x40000000
CP2: incorrect measurement unit
31
0x80000000
CP1: incorrect measurement unit
Figure 2.7.4.1.1: Definition of the status for register 5158, 5190 and 5318 (see Figure 2.7.4.1.2 and
2.7.4.2.1).
Start
register
Number of
registers
Reg1 / Reg2
Reg3 / Reg4
Reg5 / Reg6
Modbus
function
code
Read
access
Write
access
5158
6
Status CP1
(see figure
2.7.4.1.1)
Physical unit of
the last
successful
calibration CP1
(always pH)
pH value of the
last successful
calibration CP1
3, 4
U/A/S
none
5190
6
Status CP2
(see figure
2.7.4.1.1)
Physical unit of
the last
successful
calibration CP2
(always pH)
pH value of the
last successful
calibration CP2
3, 4
U/A/S
none
Figure 2.7.4.1.2: Definition of register 5158 for CP1 and register 5190 for CP2.