Siemens SIMATIC S7-200

Latching
2.2 Normally Closed (NC) Contact
Getting Started - Advanced
16 Training Documents, 09/2007, A5E01469795B
2.2 Normally Closed (NC) Contact
To disable the latching function, input I0.1 must break the current path when operated. If a
current path is interrupted (i.e. state "0" exists) when a switch is operated, this is referred to
as an NC contact.
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An element must be inserted
which works as an NC
contact in the ladder diagram
when there is 24 V DC
("true") at input I0.1.
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