LD Language Elements

Example 1

Creating a timer device for a stairway.

The stairway light should remain on for two minutes and thirty seconds when one of the push buttons is activated.

On each floor, the buttons are linked to the I1 input of the smart relay.

The stairway light is linked to the Q4 output of the smart relay.

You would write the following program:

------I1-------

TT1

------I2-------

RT1

------T1-------

[Q4

To obtain the desired operation, you should use a type B timer (On pulse one shot),

and configure the duration of the timer for 2 minutes 30 seconds. To thus configure the timer duration, choose the time units M : S and enter the value 02:30 for the

preset value t.

Illustration: Timer's configuration screen:

T T 1

 

B

R T11

 

M : S

T 1

 

t

t =

0 2 : 3 0

 

 

-

+

 

 

Menu / OK

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SR2MAN01 11/2007

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Image 97
Schneider Electric SR2MAN01 user manual Example, Preset value t Illustration Timers configuration screen