Siemens SINUMERIK 802S, Start-Up

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Start-Up
4.3 Starting up the PLC
4-68
SINUMERIK 802S
6FC5 597–2AA00–0BP2 (01.02)
PLC project
In any case, the PLC 802 Programming tool manages one project (logic
operations, symbols and comments). The download function is intended to store all important
information of a project in a control system.
The control system is able store max. 4,000 instructions and 1,000 symbols. The
required PLC memory is influenced by the following components:
S
Number of instructions
S
Number and length of the symbol names
S
Number and length of the comments
S7–200 ladder diagram
A ladder diagram is a graphical programming language similar to electric circuit diagrams.
When creating a program using the ladder diagram form, then you will work with graphical
components to create the networks of your logics. To create your program, you can use the
following elements:
S
Contacts constitute a switch through which the current can flow. Current, however, will only
flow through a normally open contact if the contact is closed (logical
value 1). Current will flow through a normally closed contact or a negated contact (NOT) if
the contact is open (logical value 0).
S
Coils constitute a relay or an output which is updated by the signal flow.
S
Boxes constitute a function (e.g. a timer, counter or arithmetic operation) which is carried
out at the moment when the signal flow reaches the box.
A network consists of the elements mentioned above, forming a closed circuit. The current
flows from the left conductor bar (in the ladder diagram symbolized by a vertical line at the left
window) through the closed contacts, enabling coils or boxes.
Overview of commands
Table 4-7 Operand identifers
Operand ID Description Range
V Data V0.0 to V79999999.7 (see Table
4–8)
T Timers T0 to T15
C Counters C0 to C31
I Map of digital inputs I0.0 to I7.7
Q Map of digital outputs Q0.0 to Q7.7
M Flags M0.0 to M127.7
SM Special flags SM0.0 to SM 0.6 (see Table 4–10)
AC ACCU AC0 ... AC3