Siemens S7-300 用户手册
5 Opening the
program on the PC
48
SIMATIC S7-300 Getting Started for First Time Users
Getting Started, 04/2007, 6ZB5310-0NC02-0BA0
5.2 Opening a program
The program for controlling the conveyor belt is stored in the “conveyor” project.
1. Open the program.
The program appears in the form of ladder logic (LAD). The operations are rep-
resented as graphical symbols.
resented as graphical symbols.
LAD is a graphical program-
ming language similar to a cir-
cuit diagram.
The inputs are represented as
normally-closed and normally-
open contacts, and the out-
puts are represented as coils.
ming language similar to a cir-
cuit diagram.
The inputs are represented as
normally-closed and normally-
open contacts, and the out-
puts are represented as coils.