Siemens SIMATIC S7-1200

Getting started with S7-1200
Getting Started, 11/2009, A5E02486791-01
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Create a simple latch circuit
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You should be familiar with the standard latching
function:
 The output K0 is activated (ON) as soon as the
push-button input PB1 closes (ON).
 Because the latching circuit utilizes the state of
K0, K0 remains active (ON) after PB1 releases
(OFF).
 Pressing the push-button input PB2 deactivates
K0 (OFF).
 K0 remains OFF until push-button input PB1
closes (ON) again.
Using K0 as a parallel input to PB1 ensures that the circuit will be "latched" on until K0
turns off.
Our first exercise shows how to create a latching circuit in LAD by performing the following
tasks:
 Creating a project
 Inserting LAD instructions to create a small user program
 Associating the LAD instructions with the I/O of the CPU
 Configuring the CPU
 Downloading your user program to the CPU
 Testing the operation of the user program