Equipments (Devices) > SCA06 > Ladder > Data Transfer

Block that converts a value from a scale to another one.

Ladder Representation

SCALE_block

Block Structure

Variable Type	Name	Data type	Description
VAR_INPUT	EN	BOOL	Block enabling
	Value	BYTE USINT SINT WORD UINT INT DWORD UDINT DINT REAL	Input value to be converted
	MAX_IN	BYTE USINT SINT WORD UINT INT DWORD UDINT DINT REAL	Maximum value of input scale
	MIN_IN	BYTE USINT SINT WORD UINT INT DWORD UDINT DINT REAL	Minimum value of input scale
	MAX_OUT	BYTE USINT SINT WORD UINT INT DWORD UDINT DINT REAL	Maximum value of output scale
	MIN_OUT	BYTE USINT SINT WORD UINT INT DWORD UDINT DINT REAL	Minimum value of output scale
VAR_OUTPUT	ENO	BOOL	End of operation
VAR_OUTPUT	Result	BYTE USINT SINT WORD UINT INT DWORD UDINT DINT REAL	Output value on new scale

Operation

This block, when it has a TRUE value in EN, by setting the minimum and maximum values of the variable to be converted and the minimum and maximum values of the new scale variable, defined by the user, performs the Scale function for the conversion of the variable according to equation:

Where:

and

The graph below represents the straight linearized:

SCALE_example02

When EN has FALSE value, DST remains unchanged.

The ENO value forwards to the next Ladder block the EN value after the operation is completed.

NOTE!

- The value in MAXin must be greater than value in MINin;

- The value in MAXout must be greater than value in MINout;

- Value in Value according to: MINin ≤ Value ≤ MAXin.

Block Flowchart

Example in Ladder

SCALE_example01

The example above stores the value of the variable VALUE in Result. The block considers the equation described above and ends with success and ENO output is activated.

Example in ST

The example below displays the instructions for applying the example above in the ST language.

VAR

VALUE : INT := 8;

MAX_IN : INT := 12;

MIN_IN : INT := 5;

MAX_OUT : INT := 5;

MIN_OUT : INT := 0;

RESULT : INT;

END_VAR

RESULT := FB_SCALE(

EN:=DI1,

Value:=VALUE,

MAX_IN:=MAX_IN,

MIN_IN:=MIN_IN,

MAX_OUT:=MAX_OUT,

MIN_OUT:=MIN_OUT,

ENO=>DO1);