redPlc Node-Red nodes for the realization of Software-PLC with Ladder-Logic according to IEC 61131-3.
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Download little tutorial using redPlc: automation_using_nodered.pdf
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Install redPlc Nodes:
@redplc/node-red-redplc -
Install Module Nodes.
Module Nodes exchange data with hardware or communication
and updates the redPlc variables.
Module Nodes also creates the I, Q, IA and QA variables.
| Module-Node | Function |
|---|---|
| @redplc/node-red-time | Get System-Time or NTP-Time |
| Module-Node | Function |
|---|---|
| @redplc/node-red-rpi-gpio | GPIO digital input/output, pwm, counter with direct i/o |
| @redplc/node-red-redplc-gpiox | GPIO digital input/output using linux character device interface |
| @redplc/node-red-rpi-ads1115 | ads1115 16bit analog to digital converter |
| @redplc/node-red-rpi-mcp3424 | mcp3424 18bit analog to digital converter |
| @redplc/node-red-rpi-ds18b20 | ds18b20 temperature sensor |
| Module-Node | Function |
|---|---|
| @redplc/node-red-wago-cc100-io | Wago CC100 Controller I/O |
In this example a tank is being filled or emptied.
The process is started with the START switch
and stopped with the STOP switch.
The filling level of the tank is determined using the LOW SWITCH and HIGH SWITCH.
When the IN VALVE is activated, the tank is filled.
When the OUT VALVE is activated, the tank is emptied.
The control automatically fills and empties the tank.
This is the original Ladder Logic:
https://www.sanfoundry.com/plc-program-control-level-single-tank/
Node-Red flow file is in examples folder: Tank_Control_RaspberryPi.json
This is the pin assignment for Raspberry Pi:
| GPIO Pin | Set | Variable | Function |
|---|---|---|---|
| GPIO21 | Input/Pullup | I0.21 | START |
| GPIO20 | Input/Pullup | I0.20 | STOP |
| GPIO16 | Input/Pullup | I0.16 | LOW SWITCH |
| GPIO12 | Input/Pullup | I0.12 | HIGH SWITCH |
| GPIO23 | Output | Q0.23 | OUT VALVE |
| GPIO24 | Output | Q0.24 | IN VALVE |
| M0.0 | MASTER |
Note: All Raspberry Pi inputs are set to Pullup.
That's why the switches have to switch to ground.
Node-Red flow file is in examples folder: Tank_Control_cc100.json
This is the pin assignment for Wago Controller CC100:
| Pin | Set | Variable | Function |
|---|---|---|---|
| DI1 | Input | I0.0 | START |
| DI2 | Input | I0.1 | STOP |
| DI3 | Input | I0.2 | LOW SWITCH |
| DI4 | Input | I0.3 | HIGH SWITCH |
| DO1 | Output | Q0.0 | OUT VALVE |
| DO2 | Output | Q0.1 | IN VALVE |
| M0.0 | MASTER |
