NAiS FP1, Руководство по оборудованию

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4-2. How to Program the Programmable Controller
4-2. How to Program the Programmable
Controller
1. Making a Ladder Diagram
Originally, programmable controllers were designed as a replacement for relay-controlled systems. Therefore,
programs can be easily created with a relay sequence circuit as shown below.
■
Explanation of Movement
■
Time chart
■
I/O Allocation
The input and output addresses of the programmable controller are allocated according to the condition in the
sequence diagram.
• All relays and timers used in the sequence circuit are replaced with internal relays and timers in the programmable
controller.
Item
External input
External output
Internal relay
Timer
Name of device
Push-button switch A
Push-button switch B
Lamp
Motor
Supplemental relay
Timer
I/O assignment
X0
X1
Y0
Y1
R0
T0
Push-button
switch A
3s
Lamp
Timer contact
Motor
Push-button
switch B
Relay contacts
1) When push-button switch A is pressed, the coil of
relay R0 is energized and its contacts turn ON.
2) Since contact
1
of relay R0 supplies power to the
coil of relay R0, the coil stays energized even if
switch A is turned OFF (self-hold circuit).
3) Contact
2
of relay R0 supplies power to lamp Y0
and timer T0. The lamp turns ON and the timer starts
timing operation.
4) After the preset time (e.g., 3 s), timer contact T0 turns
ON and motor Y1 starts operation.
5) When push-button switch B is pressed, the coil of
relay R0 is de-energized and all the power turns OFF.
T0 Y1
Ladder diagram on screen
of NPST-GR Software
(logic for programming)
TMX 30
0
R0 Y0
R0
X0 R0
Relay sequence circuit
You can make a ladder
program by converting
the contact symbols.
R
Push button
switch A
Push button
switch B
Relay coil
R
R
Relay contact 1
L
Lamp
T
Timer coil
Relay contact 2
M
Motor
T
Timer contact
X1