Hamilton Electronics EPHUM011 manual Reading the Calibration Status

pH ARC Sensors Modbus RTU Programmer’s Manual (EPHUM011)

2.7.4Reading the Calibration Status

2.7.4.1Reading 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	Number of	Reg1 / Reg2	Reg3 / Reg4	Reg5 / Reg6	Modbus	Read	Write
register	registers				function	access	access
					code
5158	6	Status CP1	Physical unit of	pH value of the	3, 4	U/A/S	none
		(see figure	the last	last successful
		2.7.4.1.1)	successful	calibration CP1
			calibration CP1
			(always pH)
5190	6	Status CP2	Physical unit of	pH value of the	3, 4	U/A/S	none
		(see figure	the last	last successful
		2.7.4.1.1)	successful	calibration CP2
			calibration CP2
			(always pH)

Figure 2.7.4.1.2: Definition of register 5158 for CP1 and register 5190 for CP2.

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