TIME Constants¶

You use TIME constants to operate the standard timer modules. TIME is a 32-bit IEC 61131-3 compliant time constant. In addition to TIME, CODESYS also supports LTIME as a time base for high-resolution timers. LTIME is a 64-bit time constant that extends the standard with a resolution in nanoseconds.

Syntax of time constants

t#<time declaration>

As an alternative, you can use the following styles of syntax instead of “t#”: T#, time, TIME.

You use this time declaration for all of the units of time listed below. These units must be in the order as shown below; however, not all units have to be declared.

d: days

h: hours

m: minutes

s: seconds

ms: milliseconds

Examples of correct use of time constants in an ST assignment:

`TIME1 := T#14ms;`
`TIME1 := T#100s12ms;`	`(Overflow in the highest components is permitted.)`
`TIME1 := t#12h34m15s;`

Examples of incorrect use:

`TIME1 := t#5m68s;`	`(overflow at a lower position)`
`TIME1 := 15ms;`	`(T# missing)`
`TIME1 := t#4ms13d;`	`(incorrect order of time dimensions)`

Syntax of LTIME constants

LTIME#<time declaration>

In the time declaration, you can use the same units of time as for TIME constants. You can also use the the following units:

µs: microseconds

ns: nanoseconds

Examples of correct use of LTIME constants in an ST assignment:

`LTIME1 := LTIME#1000d15h23m12s34ms2us44ns`
`LTIME1 := LTIME#3445343m3424732874823ns`