Immediate Contacts - Siemens SIMATIC S7-200 System Manual

Immediate Contacts

L
A
D
F
B
D
S
LDI
T
AI
L
OI
LDNI
ANI
ONI
221 222
In STL, the Normally Open Immediate contact is represented by the Load Immediate, And
Immediate, and Or Immediate instructions. These instructions Load, AND, or OR the physical
input value to the top of the stack immediately.
In STL, the Normally Closed Immediate contact is represented by the Load Not Immediate,
And Not Immediate, and Or Not Immediate instructions. These instructions immediately
Load, AND, or OR the logical NOT of the value of the physical input point to the top of the
stack.
Inputs/Outputs
bit (LAD, STL) I
Input (FBD) I
S7-200 Programmable Controller System Manual
A5E00066097-02
The immediate instruction obtains the physical input
value when the instruction is executed, but the
bit
process-image register is not updated.
I
The Normally Open Immediate contact is closed (on)
bit
when the physical input point (bit) is 1.
/I
The Normally Closed Immediate contact is closed (on)
when the physical input point (bit) is 0.
In LAD, normally open and normally closed immediate
instructions are represented by contacts.
In FBD, normally open immediate instructions are
represented by the immediate indicator in front of the
bit
operand tic. The immediate indicator may not be present
bit
when power flow is used. The instruction can be used to
bit
manipulate physical signals in the same manner as
bit
ladder contacts.
bit
bit
In FBD, normally closed immediate instructions are also
represented by the immediate indicator and negation
symbol in front of the operand tic. The immediate
224 226
indicator cannot be present when power flow is used.
The normally closed instruction is constructed by placing
the negation symbol on the stem of the input signal.
Operands
SIMATIC Instructions
Data Types
BOOL
BOOL
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