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• SUB_LDT_LDT

SUB_LDT_LDT

Type	Function
Description	Subtracts two times (LDATE_AND_TIME) and delivers a duration (LTIME) as result. The point in time connected to IN2 is subtracted from the point in time connected to IN1. The result duration is positive if the point in time at IN1 is more recent (greater) than the point in time at IN2. The result is negative if the point in time at IN1 is less recent (smaller) than the point in time at IN2. Note This function is not extendable, no further inputs can be added.
Notes	When the subtraction result exceeds the permissible range of the output value, an overflow occurs.
Parameters	Inputs IN1 Data type: LDATE_AND_TIME Description: Point in time to subtract from. IN2 Data type: LDATE_AND_TIME Description: Point in time subtracted from IN1. Output Out Data type: LTIME Description: Difference (duration) of the two input points of time.
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 Overflow Overflow value
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. If the result is a negative LTIME value, ENO is set to TRUE as long as the range of LTIME is not exceeded Further Info See the topic "General information on execution control with EN/ENO" for further details.