Curve_20XY_Real_Real

Curve_20XY_Real_Real (FB)

FUNCTION_BLOCK Curve_20XY_Real_Real

Short description

Input of 20 value pairs (support points each with an X and Y value) Boundary conditions:\

1. The X values must be consecutive either strictly increasing or strictly decreasing

2. Each X value may only appear once

3. Two adjacent support points are each connected by a straight line Typical application: Calculation of the performance of a heat pump depending on the outside temperature

Representation

Interfaces

Inputs

Name	Data type	Value range	Initial value	Function
rInputValue	REAL		0	Current value of the input variable

Outputs

Name	Data type	Value range	Initial value	Function
rOutputValue	REAL		0.0	Current value of the output variable
eOrderXValues	eCurve_20XY_Real_Real_Order		eCurve_20XY_Real_Real_Order.Invalid	Order of the X values (increasing / decreasing)
eError	eCurve_20XY_Real_Real_Error		eCurve_20XY_Real_Real_Error.No_Error	Cause of error
xError	BOOL		FALSE	Error state ( TRUE = error )

Setpoints / parameters

Name	Data type	Value range	Initial value	Function
rOutputValue_Subst	REAL		-1000	Substitute value of the output variable in case of error
rOutputValue_Min	REAL		0	Absolute minimal value of the output variable
rOutputValue_Max	REAL		100	Absolute maximal value of the output variable
rSP1_X	REAL		1	Support point 1 - X value
rSP1_Y	REAL		2	Support point 1 - Y value
rSP2_X	REAL		2	Support point 2 - X value
rSP2_Y	REAL		4	Support point 2 - Y value
rSP3_X	REAL		3	Support point 3 - X value
rSP3_Y	REAL		6	Support point 3 - Y value
rSP4_X	REAL		4	Support point 4 - X value
rSP4_Y	REAL		8	Support point 4 - Y value
rSP5_X	REAL		5	Support point 5 - X value
rSP5_Y	REAL		10	Support point 5 - Y value
rSP6_X	REAL		6	Support point 6 - X value
rSP6_Y	REAL		12	Support point 6 - Y value
rSP7_X	REAL		7	Support point 7 - X value
rSP7_Y	REAL		14	Support point 7 - Y value
rSP8_X	REAL		8	Support point 8 - X value
rSP8_Y	REAL		16	Support point 8 - Y value
rSP9_X	REAL		9	Support point 9 - X value
rSP9_Y	REAL		18	Support point 9 - Y value
rSP10_X	REAL		10	Support point 10 - X value
rSP10_Y	REAL		20	Support point 10 - Y value
rSP11_X	REAL		11	Support point 11 - X value
rSP11_Y	REAL		22	Support point 11 - Y value
rSP12_X	REAL		12	Support point 12 - X value
rSP12_Y	REAL		24	Support point 12 - Y value
rSP13_X	REAL		13	Support point 13 - X value
rSP13_Y	REAL		26	Support point 13 - Y value
rSP14_X	REAL		14	Support point 14 - X value
rSP14_Y	REAL		28	Support point 14 - Y value
rSP15_X	REAL		15	Support point 15 - X value
rSP15_Y	REAL		30	Support point 15 - Y value
rSP16_X	REAL		16	Support point 16 - X value
rSP16_Y	REAL		32	Support point 16 - Y value
rSP17_X	REAL		17	Support point 17 - X value
rSP17_Y	REAL		34	Support point 17 - Y value
rSP18_X	REAL		18	Support point 18 - X value
rSP18_Y	REAL		36	Support point 18 - Y value
rSP19_X	REAL		19	Support point 19 - X value
rSP19_Y	REAL		38	Support point 19 - Y value
rSP20_X	REAL		20	Support point 20 - X value
rSP20_Y	REAL		40	Support point 20 - Y value

Function description

The output variable 'rOutputValue' is calculated cyclically based on the input variable 'rInputValue' and the characteristic curve defined by the 20 support points, provided no error is present ( xError = FALSE ). It is limited by the configurable absolute minimum ( rOutputValue_Min ) and maximum values ( rOutputValue_Max ). In case of error ( xError = TRUE ) the fixed substitute value 'rOutputValue_Subst' is output on the output variable 'rOutputValue'. The X values of the 20 support points must meet the following boundary conditions: 1) The X values must be consecutive either strictly increasing or strictly decreasing 2) Each X value may only appear once 3) Two adjacent support points are each connected by a straight line The update of the characteristic curve is performed once immediately after initialization or once after every change of the support points. In case of error (identical X values, X values not strictly increasing / decreasing) a corresponding cause of error is indicated at the output 'eError'. At the same time the fixed substitute value 'rOutputValue_Subst' is output on the output variable 'rOutputValue'. The output 'xError' is active ( = TRUE ) if an error is signaled at the output 'eError'.\

Representation of an example characteristic curve

CODESYS

InOut:

Scope	Name	Type	Initial
Input	rInputValue	REAL	0
Output	rOutputValue	REAL	0
Output	eOrderXValues	eCurve_20XY_Real_Real_Order	eCurve_20XY_Real_Real_Order.Invalid
Output	eError	eCurve_20XY_Real_Real_Error	eCurve_20XY_Real_Real_Error.No_Error
Output	xError	BOOL	FALSE
Input Const	rSP20_Y	REAL	40
Input Const	rSP20_X	REAL	20.0
Input Const	rSP19_Y	REAL	38.0
Input Const	rSP19_X	REAL	19.0
Input Const	rSP18_Y	REAL	36.0
Input Const	rSP18_X	REAL	18.0
Input Const	rSP17_Y	REAL	34.0
Input Const	rSP17_X	REAL	17.0
Input Const	rSP16_Y	REAL	32.0
Input Const	rSP16_X	REAL	16.0
Input Const	rSP15_Y	REAL	30.0
Input Const	rSP15_X	REAL	15.0
Input Const	rSP14_Y	REAL	28.0
Input Const	rSP14_X	REAL	14.0
Input Const	rSP13_Y	REAL	26.0
Input Const	rSP13_X	REAL	13.0
Input Const	rSP12_Y	REAL	24.0
Input Const	rSP12_X	REAL	12.0
Input Const	rSP11_Y	REAL	22.0
Input Const	rSP11_X	REAL	11.0
Input Const	rSP10_Y	REAL	20.0
Input Const	rSP10_X	REAL	10.0
Input Const	rSP9_Y	REAL	18.0
Input Const	rSP9_X	REAL	9.0
Input Const	rSP8_Y	REAL	16.0
Input Const	rSP8_X	REAL	8.0
Input Const	rSP7_Y	REAL	14.0
Input Const	rSP7_X	REAL	7.0
Input Const	rSP6_Y	REAL	12.0
Input Const	rSP6_X	REAL	6.0
Input Const	rSP5_Y	REAL	10.0
Input Const	rSP5_X	REAL	5.0
Input Const	rSP4_Y	REAL	8.0
Input Const	rSP4_X	REAL	4.0
Input Const	rSP3_Y	REAL	6.0
Input Const	rSP3_X	REAL	3.0
Input Const	rSP2_Y	REAL	4.0
Input Const	rSP2_X	REAL	2.0
Input Const	rSP1_Y	REAL	2.0
Input Const	rSP1_X	REAL	1.0
Input Const	rOutputValue_Max	REAL	100.0
Input Const	rOutputValue_Min	REAL	0.0
Input Const	rOutputValue_Subst	REAL	-1000.0