LD Language Elements

Use as a Contact The contact associated with the fast counter indicates whether the preset value (TO mode) or zero (FROM mode) has been reached.

It may be used as many times as necessary as many times as necessary in the program. It may be used according to 2 modes: normally open or normally closed, described below.

Normally open mode:

Symbol of the normally open contact associated with the fast counter:

K1

The contact is conducting when:

zthe current value of the counter has reached the preset value (TO mode),

zthe current value of the counter has reached the 0 value (FROM mode).

Normally closed mode:

Symbol of the normally closed contact associated with the fast counter:

k1

The contact is conducting as long as :

zthe current counter value has not reached the preset value, if the counter is in TO mode,

zThe counter current value has not reached 0, if the counter is in FROM mode,

Example: Lighting a LED connected to fast counter no. 1 output (TO mode).

K1

 

[ Q1

 

 

 

 

When the preset value has been reached: The LED is lit; otherwise it is off.

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SR2MAN01 11/2007

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