The AnalogControlFunctionWithRelativeTargetValueType supports applications where the target value is typically modified by relative increments or decrements.

Examples of its usage include position controllers where the actuator needs to modify its position relative to the last defined position by a specific amount, or dispenser controllers that are responsible for aspirating or dispensing a certain volume of fluid.

The optional DecreaseRate and IncreaseRate variables can be utilized to customize the dynamics of the resulting action based on application-specific requirements. These variables allow for adapting to factors such as viscosity when aspirating or dispensing fluids.

AnalogControlFunctionWithRelativeTargetValueType is formally defined in Table 100.

Table 100 – AnalogControlFunctionWithRelativeTargetValueType Definition

Attribute	Value
BrowseName	AnalogControlFunctionWithRelativeTargetValueType
IsAbstract	False
References	Node Class	BrowseName	DataType	TypeDefinition	Other
Subtype of the AnalogControlFunctionType defined in 7.6.5
0:HasComponent	Variable	DecreaseRate	Double	AnalogUnitRangeType	O
0:HasComponent	Method	ModifyTargetValueBy			O
0:HasComponent	Variable	IncreaseRate	Double	AnalogUnitRangeType	O
Conformance Units
LADS AnalogControlFunctionWithRelativeTargetValueType

The ModifyTargetValueBy Method is used to modify the current TargetValue by a relative amount. The resulting value shall be limited to the TargetValue’s allowed range (EURange).

The direction of the action is application dependent and is controlled by the sign of the provided value. For instance, negative values may indicate moving left and positive values may indicate moving right, or positive values may be used for aspirating a defined volume while negative values may be used for dispensing a defined volume.

The signature of this Method is specified below. Table 101 and Table 102 specify the Arguments and AddressSpace representation, respectively.

Signature

ModifyTargetValueBy (

[in]0:DoubleValue

)

Table 101 – ModifyTargetValueBy Method Arguments

Argument	Description
Value	Relative value by which the target value will be changed. The resulting value will typically be limited to the target-value’s allowed range. Provided values can be positive or negative.

Table 102 – ModifyTargetValueBy Method AddressSpace Definition

Attribute	Value
BrowseName	ModifyTargetValueBy
References	Node Class	BrowseName	DataType	TypeDefinition	ModellingRule
0:HasProperty	Variable	0:InputArguments	0:Argument[]	0:PropertyType	0:Mandatory