Short summary

Name	`DIV_TIME`
→POU type	→function
Category	IEC-block, Time, block with internal error diagnostic
Conform to →IEC-standard	no restrictions
Graphical interface
Available since	version 1.19.0 (for logi.CAD 3)

Functionality

The block divides the time value entered at input IN1 by a numerical value entered at input IN2 (= IN1 / IN2). The block returns the result of this division in format TIME.

Unexpected calculation of values with a REAL value at input IN2 due to a higher calculation precision

If a REAL value is connected to input IN2, a LREAL value is used for the internal calculation (instead of a REAL value). Thus, a higher calculation precision is achieved than is actually required for REAL. The calculation of values with a lower calculation precision for REAL values is not supported.

Example: With a REAL value for IN2, the value TIME#3000d is calculated. This calculation is executed due to the higher calculation precision. If the same value is connected to IN2 but with data type LREAL, the same value TIME#3000d is calculated.
In comparison: In case of an internal calculation with REAL, the value TIME#2999d23h59m51s808ms would be returned.

Workaround: If you want to calculate precise values, connect the input IN2 of the DIV_TIME block with a LREAL value.

No check of invalid connections

For this block, invalid connections are not checked by logi.CAD 3 (except for the checks listed under "Internal error diagnostic for block"). Therefore, enter code in your application to detect invalid connections (e.g. IF-statements). See "Examples for invalid Connections".

See "IEC-blocks for the application" for information what the consequences of an invalid connection might be.

Inputs, return value

	Identifier	→Data type	Description
Inputs:	`IN1`	`TIME`	time value
Inputs:	`IN2`	`REAL`, `LREAL`, `USINT`, `UINT`, `UDINT`, `ULINT`, `SINT`, `INT`, `DINT` or `LINT` (corresponds to →generic data type `ANY_NUM`) ⁽¹⁾	numerical value
Return value:	–	`TIME`

⁽¹⁾ = DIV_TIME uses the highest possible accuracy for the calculations. That means: If a REAL value is connected to IN2, logi.CAD 3 uses a LREAL value for the calculation and a division by a REAL value might result in a not expected result. If you need large values or values with many decimal places, best practice is to use a LREAL value.

Input EN and output ENO are available when →calling the block. See "Execution control: EN, ENO" for information on input EN and output ENO.

See:

"Blocks for safe logic" whether this block is supported for developing safety-relevant applications.
"Highlighting safe logic in the FBD-editor" for the effects when using the block as a block for safe logic .

Internal error diagnostic for block

The block checks for a division by 0 before it is executed.
In this error case, the output ENO of the block is set to value FALSE (or an equivalent).

Example for usage within ST-editor

The calculated values are evaluated by using the Assert block .

FUNCTION_BLOCK ExampleDivTime
  VAR
    result : TIME;
  END_VAR
 
  result := DIV_TIME(IN1 := T#1m40s, IN2 := 2.0);
 
  Assert(result = TIME#50s); 
END_FUNCTION_BLOCK

When creating your application within the ST-editor, enter a call of a block by typing the text as requested by the syntax or use Content Assist.

Examples for invalid connections

An invalid connection due to →overflows or →underflows might occur during a calculation using DIV_TIME. As your used →target system might influence the usage of →time literals in logi.CAD 3 (see "Properties and restrictions specific to the target system"), an overflow/underflow might occur for different return values when using different target systems.

Example for invalid connections

DIV_TIME(IN1 := TIME#89468321d19h, IN2 := REAL#3.0e-30); (* For the built-in PLC, this calculuation returns a negative value. *)