Schneider Electric SR2MAN01 사용자 설명서

LD Language Elements

SR2MAN01 11/2007

89

The 

Discrete Inputs can be used exclusively as contacts in the program. 

These contacts represent the status of the input for the smart relay connected to a 
sensor (push button, switch, sensor, etc.).

The contact number corresponds to the number of terminals of the associated input: 
1 to 9, then A to R (except for letters I, M and O) according to the smart relay and 
the possible extension.

This contact may use the direct state of the input (normally open mode) or its inverse 
state (mode normally closed), see below.

Symbol of a normally open contact: 

A normally open contact corresponds to the use of the 

direct state of the input. If the 

input is 

supplied, the contact is said to be conducting.

Example: Using a pushbutton to switch a lamp on and off. 

If input 

1 is supplied, contact I1 is closed, and coil Q1 is activated.

Symbol of a normally closed contact: 

A normally closed contact corresponds to the use of the 

reverse state (logical 

complement of the direct state) of the input. If the input is 

supplied, the contact is 

said to be 

non-conducting.

Example: Controlling a lamp using an input in reverse state. 

If input 

1 is supplied, contact i1 is open, and coil Q1 is non-activated.