Siemens SIMATIC S7-300 User Manual

Page 34

3 Installing and

wiring the hardware

SIMATIC S7-300 Getting Started for First Time Users

Getting Started, 04/2007, 6ZB5310-0NC02-0BA0

Testing the connections

Now, test your wiring to verify that it is functioning properly.
For this purpose, take turns pressing the momentary contact switches and
observe the LEDs on the inputs of the CPU. Whenever an input is activated, the
corresponding LEDs always light up.

• Press the green momentary contact switch for “Motor ON”. The LED of input

0.0 (terminal 2) will light up.

• Press the red momentary contact switch for “Motor OFF”. The LED of input

0.1 (terminal 3) will light up.

• Press the right momentary contact switch for “Clockwise rotation”. The LED of

input 0.2 (terminal 4) will light up.

• Press the left momentary contact switch for “Counterclockwise rotation”. The

LED of input 0.3 (terminal 5) will light up.

You have installed, wired, and tested all components. Next, you will create the
control structure in STEP 7 Lite and download the configuration to the
CPU 312C.

Note
To make the example easier
to follow, we will use colored
momentary contact switches.
You can implement the exam-
ple with commercially avail-
able momentary contact
switches of any color.