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LIMIT

Type	Function
Description	Limits the value of the input parameter IN to the value range defined by the input parameters MN (minimum limit) and MX (maximum limit) as follows: OUT := MIN(MAX(IN,MN),MX) where the function MIN determines the minimum limit for the output value and the function MAX the maximum limit for the output value. The value connected to IN is written to the output if the value is in the range of MN and MX. If the value at IN1 is smaller than the MN value (IN1 < MN), the MN value is written to the output. If the value at IN1 is greater than the MX value (IN1 > MX), the MX value is written to the output.
Notes	The function provides implicit data type conversion at its input and output parameters according to the rules defined by the IEC 61131 standard. The function is an overloaded function. It can operate on various input data types. The function is not extendable, no further inputs can be added.
Parameters	Inputs MN Data type: ANY_ELEMENTARY Description: Minimum limit. IN Data type: ANY_ELEMENTARY Description: Input value. MX Data type: ANY_ELEMENTARY Description: Maximum limit. Output OUT Data type: ANY_ELEMENTARY Description: Output value.
Error behavior	Error behavior The following table shows the errors which may occur while executing the function and the value returned by the function in the corresponding error case. Error case Output value MIN > MAX MIN(MAX(IN,MN),MX) (See the function description above) Any input = NaN IN value Any input = Inf+ IN value Any input = Inf- IN value Resulted string too short Empty string Note String comparison: In case of a string error, the function returns the empty string ''. Furthermore, the controller runtime logs the error in its error catalog and a corresponding error message is shown in the Error List. Note Controller stop on string error: The controller can be automatically stopped when a string error occurs. This allows you to locate the error in your project. To enable the automatic stop of the controller in case of a string error, activate the button in the Cockpit toolbar of the controller.
Additional information	EN/ENO behavior The POU is only executed if TRUE is applied to the EN input. If EN = FALSE, the POU is not executed and ENO = FALSE indicates the inactivity. If any of the errors listed under "Error behavior" occurs while executing the function, ENO is set to FALSE. Further Info See the topic "General information on execution control with EN/ENO" for further details.