ElPercha/PLsi

PLsi Project Objectives

Create a PLC & HMI with the following main characteristics:

To not require external systems such us Laptops or Cellphones to be programmed
To be used on Classroom for educational purposes, IoT applications or industrial low risk applications
Software and Hardware with Industrial performance and features
Forever Open Source and Open Hardware
Focus on Low Cost, V0 hardware estimated in less than $20

Main characteristics:

Easy to build, no SMD components. DIY!
ESP32 Processor
- Dual Core @240MHZ
- Wi-Fi connectivity
2.8" 320x240 Touchscreen Display
8 Hardware Inputs 5-24VDC Isolated with status led
6 Hardware Relay Outputs with status led. Max 10A, external fuse required
Different combinations of Digital and Analog I/O using the same board
- Analog I/O range: 0-5V
Removable Terminal blocks
USB 5Vdc main power supply
I2C port for hardwired expansions
SD Card slot
3D printed housing model including DIN rail mounting bracket

Main functionalities:

PLC Ladder Logic Instruction set:
- 35 instructions
- Boolean instructions full set
- Timers and Counters full set
- Comparisons full set
- 16 bit math functions
PLC Memory Areas:
- 2000 Marks (M)
- 200 Counters (C)
- 300 Timers (T)
- 10000 Registers 16bits (D)
PLC Program size:
- Up to 400 networks of 6x5 cells (12K boolean instructions)
- Up to 4 PLC programs stored on internal memory (max. 400 networks each)
PLC Program Editor
- Online Edition (with PLC running)
- Row, Column and Network Editor
- Network Navigation
PLC performance and control
- Scan time of 2.3ms for 2000 Boolean instructions
- Processor Core 1 runs Ladder Logic exclusively
- RUN/STOP with user confirmation
Display functions:
- PLC Programming and debugging
- PLsi Configuration
- HMI
  - "Fix" version implemented (User cannot edit memory areas nor texts)
  - Screen 1: 8 Switches M500 to M507
  - Screen 2: 8 Buttons M510 to M517
  - Screen 3: 8 User Input Values D500 to D507
  - Screen 4: Local I/O visualization
  - Screen 5: 8 Indicators M520 to M527
Communications:
- Wi-Fi configuration. Only DHCP
- SSID scanning functionality
Firmware update via Web Page
Analog Inputs and Outputs
- Selectable via Configuration page

Wiring, configuration and programming: PLsi v0 User Manual (on contruction)

DIY components pricing is included here
- This pricing considers to purchase some bulk quantities
Two industrial protocols are planned to be added in future releases
- S7 connection Issue #26
- Modbus TCP Issue #27
Not planned yet
To be included on Hardware V1 Issue #35
The I2C expansion port is available to connect wired expansions
- Wi-Fi expansion modules are also feasible
- Not in the roadmap yet
A Web HMI hosted on the PLsi unit is proposed on Issue #42

The PLsi board v0 is designed to support, at least, 2 different configurations:

All Digital I/O
- 8 Digital Inputs
- 6 Digital Relay Outputs
Digital and Analog I/O
- 6 Digital Inputs
- 4 Digital Relay Outputs
- 2 Analog Inputs 0-5V
- 2 Analog Outputs 0-5V

Check the drawing and the Hardware Manual for more details on how to build the 2 different models using the same board

Supply Voltage: 5V 1A (recommended 2A)
- Standard Micro USB type B connector
External fuse or fuses are required to protect the Outputs circuits
- Fuse size has to be calculated considering a total MAX consumtion of 10A
SD Card is optional, it has no functionality implemented in Fimware v0.00.03
I2C Port is optional, it has no functionality implemented in Fimware v0.00.03