Background
In many industrial settings, full-scale PLCs are overkill when the logic is simple, the I/O count is small, and high precision isn’t required. The IOy BL190 module from Beilai (BLIoT) is one such device: it combines I/O, Modbus TCP communication, and some logic capabilities, making it a cost-effective PLC alternative for “if… then…” type control.
Scenario / Requirement
A conveyor motor that can be started via a “Start” button and stopped via a “Stop” button.
A safety gate that if opened, forces the conveyor to stop.
Two pumps, Pump A and Pump B: when Pump A is running, Pump B must be prevented from starting (simple interlock).
Hardware / Configuration Using BL190
Use one BL190 module.
Attach the following Y-series I/O boards:
| Board | Function | Used For |
|---|---|---|
| Y11 (8 DI) | Digital Inputs | “Start” button (DI1), “Stop” button (DI2), safety gate sensor (DI3) etc. |
| Y21 (Digital Output) | Digital Outputs | Conveyor motor control (DO1), Pump A (DO2), Pump B (DO3) etc. |
Power the module with 24 V DC. Ensure wiring is correct and protected. Use the 2 Ethernet ports: one upstream to the control network / HMI / supervisory device, another for cascading or network extension if needed. Use RS-485 if needed (e.g. collecting data from meters or other devices).
Logic (if … then … rules) Implementation
These are configured using the BL190’s built-in web interface or logic configuration:
If DI1 (Start Button) is closed → set DO1 (Conveyor Motor) ON.
If DI2 (Stop Button) is closed → set DO1 OFF.
If DI3 (Safety Gate) is open → force DO1 OFF immediately.
If DO2 (Pump A) is ON → block any command that would set DO3 (Pump B) ON.
| Feature | Description |
|---|---|
| Communication & Protocols | Modbus TCP over Ethernet (2×RJ45 ports, 10/100 Mbps, adaptive) + isolated RS-485 port supporting Modbus RTU master mode. |
| I/O Expansion | 1 to 3 “Y-series” I/O boards can be mounted. Mix & match digital inputs (DI), digital outputs (DO), analog inputs (AI), RTD/PT sensor inputs, etc. Example configurations: 24 DI (3× Y11 boards), or 8 DI + 4 AI + 2 PT modules. |
| Logic & Edge Processing | Built-in web server allows fast implementation of register operations and logic control ("if… then…" rules). Also supports arithmetic & logic operations between I/O signals and constant values. |
| Reliability / Environmental | Industrial grade: operates −45°C to +80°C; electrical isolation; EMC/EMI certified; hardware watchdog for stability. |
| Power Supply | 24 V DC supply. |
| Protocol Features | Supports Modbus TCP server mode; supports key Modbus functions (1,2,3,4,5,6,15,16). Multiple clients can access the module. Also includes RS-485 serial collection (RTU master), and conversions between RTU <→ TCP if needed |
Result
With these simple logic rules, the BL190 module executes local control reliably without the need for a PLC. It provides:
Stable operation for basic interlock and sequence control
Easy configuration through if–then rules
Reduced hardware and deployment costs compared to traditional PLC solutions
Conclusion
The IOy (BL190) is ideal for projects requiring basic I/O linkage, interlocks, or simple device automation, delivering both reliability and cost efficiency.
