Hamilton Electronics EPHUM011 manual 3 PA12 Moving Average R, Description of PA12 Moving Average R

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

2.6.3 PA12: Moving Average R

pH ARC Sensors allow to have a separate moving average on secondary measurement values:

Glass resistance

Reference resistance

The moving average can be applied on 1 to 16 3-s measurement values. The default value is 4. Especially if high resistances are measured, it is recommended to choose a higher moving average.

2.6.3.1Description of PA12 (Moving Average R)

In register 3456, a plain text ASCII description of PA12 is given.

Start	Number of	Reg1 … Reg8	Modbus	Read	Write
register	registers	16 ASCII characters	function code	access	access
3456	8	Description of PA12	3, 4	U/A/S	none

Figure 2.6.3.1.1: Definition of register 3456.

Command: Moving average text		Modbus address: 3456	Length: 8	Type: 3	Read
Parameter:	Text
Format:	Character
Value:	Moving average R

Figure 2.6.3.1.2: Example to read the description for “Moving average R“.

2.6.3.2Selecting the Physical Unit and Writing the Value for PA12

In register 3464, the available physical units for PA12 are defined.

Start	Number of		Reg1 / Reg2		Modbus		Read	Write
register	registers		(bitwise defined)		function code		access	access
3464	2		Available physical units for PA12		3, 4		U/A/S	none
Figure 2.6.3.2.1: Definition of register 3368.
Command: Moving average av. units				Modbus address: 3464	Length: 2	Type: 3		Read
Parameter:		Units
Format:		Hex
Value:		0x01

Figure 2.6.3.2.2: Example to read the available physical units for PA12. The only one available here is “none”(0x01). For the definition of the physical units see chapter 2.5.1.

Start	Number of	Reg1 / Reg2	Reg3 / Reg4	Modbus	Read	Write
register	registers	(bitwise defined)		function code	access	access
3466	4	Select physical unit	Value for PA12	16	none	S
		for PA12	(1-16, default: 4)

Figure 2.6.3.2.3: Definition of register 3466. Only one bit for the physical unit can be set. PA12 can be set to the values 1-16.

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