node-red-ermangizer-modbus

Node-RED ERMANGIZER Modbus Node

A custom Node-RED node for decoding ERMANGIZER frequency converter Modbus RTU protocol messages according to the official protocol specification.

Features

• 🚀 Multiple Input Formats: Supports Buffer, Hex String, and Number Array inputs
• 🔍 Auto Detection: Automatic input type detection
• 📊 Two Output Formats: Detailed (full metadata) and Simplified (values only)
• ✅ CRC Verification: Ensures data integrity with CRC-16 checks
• 🛡️ Error Handling: Comprehensive error handling with descriptive messages
• 📋 Complete Protocol Support: Decodes all registers from the ERMANGIZER protocol
• 🌐 TypeScript: Written in TypeScript for better maintainability

Supported Registers

The node decodes all registers defined in the ERMANGIZER Modbus RTU protocol:

Read-Only Registers

• output_frequency - Current output frequency (0.1 Hz)
• output_current - Current output current (0.1 A)
• input_voltage - Current input voltage (V)
• temperature - Current temperature (°C)
• pressure - Actual pressure value (0.01 bar)
• error_code - Error code with descriptions
• status_code - Status code with bit-level decoding

Read-Write Registers

• factory_reset - Restore factory settings
• initial_pressure_diff - Initial pressure difference (0.01 bar)
• water_shortage_pressure - Pressure value during water shortage (0.01 bar)
• water_shortage_time - Water shortage time (s)
• carrier_frequency - Carrier frequency selection
• accel_decel_time - Acceleration and deceleration time (0.1 ms)
• pressure_tolerance - Allowable pressure error (0.01 bar)
• min_shutdown_freq - Minimum shutdown frequency (0.1 Hz)
• continuous_operation - Enable continuous operation
• measurement_range - Measurement range selection (bar)
• overheat_setting - Overheat setting (°C)
• direction_setting - Set rotation direction
• local_address - Local Modbus address

Control Registers

• set_pressure - Set pressure value (0.01 BAR)
• status_command - Command status code

Installation

npm Installation

cd ~/.node-red
npm install node-red-ermangizer-modbus

Then restart Node-RED.

Usage

Basic Setup

• Add the node to your flow from the palette (category: "parser")
• Configure settings:
  • Name: Optional node name
  • Input Type: Auto-detect or specify format
  • Output Format: Choose between Detailed or Simplified
• Connect input: Connect to any node that outputs Modbus RTU data
• Connect output: Process the decoded data in subsequent nodes

Input Formats

The node accepts three input formats:

1. Buffer (Recommended)

// From serial port or TCP Modbus connection
msg.payload = buffer; // Raw Buffer object

2. Hex String

// Hexadecimal string (spaces optional)
msg.payload = "3f0300010016911a";
// or
msg.payload = "3f 03 00 01 00 16 91 1a";

3. Number Array

// Array of byte values
msg.payload = [0x3f, 0x03, 0x00, 0x01, 0x00, 0x16, 0x91, 0x1a];

Output Formats

Detailed Format (Default)

{
  "slave_address": 63,
  "function_code": 3,
  "function_name": "Read Holding Registers",
  "raw_data": "3F0300010016911A",
  "timestamp": "2024-01-15T10:30:00.000Z",
  "registers": {
    "output_frequency": {
      "value": 50.0,
      "raw_value": 500,
      "unit": "0.1 Hz",
      "description": "Current output frequency value",
      "address": 1,
      "read_only": true
    },
    "error_code": {
      "code": 0,
      "description": "No error",
      "raw_value": 0
    }
    // ... more registers
  }
}

Simplified Format

{
  "slave": 63,
  "function": "Read Holding Registers",
  "timestamp": "2024-01-15T10:30:00.000Z",
  "output_frequency": 50.0,
  "error_code": 0,
  "temperature": 45,
  "pressure": 2.5
  // ... more register values
}

Examples

Example 1: Reading Multiple Registers

// Input message (hex string example)
msg.payload = "3f03002c3f032c01f4000100ea0020000000000001000000000001001e000a001e004c0014000a00f00000000600550000003f38ee";

// Output (simplified format):
{
  "slave": 63,
  "function": "Read Holding Registers",
  "output_frequency": 50.0,
  "output_current": 5.0,
  "input_voltage": 234,
  "temperature": 32,
  "pressure": 0.0,
  "error_code": 0,
  "status_code": 0
}

Example 2: Error Response

// Error response example
msg.payload = "3f8302a13d";

// Output:
{
  "slave_address": 63,
  "function_code": 131,
  "function_name": "Error Response",
  "error": {
    "code": 2,
    "description": "Modbus Error: Illegal Data Address",
    "modbus_error": true
  }
}

Error Codes

The node decodes all ERMANGIZER error codes:

Code	Description
0	No error
1	Equipment overcurrent, short circuit
2	Overload
3	Low pressure (no pressure sensor)
4	Overpressure
5	Low pressure
6	Overpressure
7	Phase loss (power phase loss)
8	Overheating
9	Insufficient power
10	Software current overload
11	Communication failure
12	Default
13	Motor locked
14	Motor phase loss
15	Motor overspeed
16	Memory failure (FLASH failure)

Status Code Decoding

The status register (0x0007) is decoded into individual bits:

{
  "water_shortage": false,  // Bit 0: 0=no water shortage, 1=water shortage
  "running": true,          // Bit 1: 0=stopped, 1=running
  "raw_value": 2           // Original register value
}

Building from Source

If you're modifying the TypeScript source:

• Install dependencies:

  npm install
  

• Build the project:

  npm run build
  

• For development with auto-rebuild:

  npm run dev
  

Troubleshooting

Common Issues

• "CRC check failed"

  • Verify the Modbus message is complete and uncorrupted
  • Check that the entire message including CRC is provided

• "Message too short"

  • Ensure the input contains at least 4 bytes (address + function code + CRC)

• "Unsupported input type"

  • Use one of the supported formats: Buffer, hex string, or number array
  • Enable auto-detection if unsure of the format

• Node not appearing in palette

  • Check that all files are in the correct location
  • Verify there are no syntax errors in the files
  • Restart Node-RED completely

Debugging

Enable Node-RED debug output to see detailed processing information:

• Add a debug node connected to the ERMANGIZER Modbus node output
• Set debug to display complete message object
• Check the Node-RED logs for any error messages

Protocol Reference

This node implements the ERMANGIZER Modbus RTU protocol as specified in:

• Document: protocol_modbus_eg-g-220-03.pdf https://www.ermangizer.ru/image/pdf/protocol_modbus_eg-g-220-03.pdf
• Baud Rate: 9600
• Data Bits: 8 bits + 1 stop bit
• Parity: None
• Device Address Range: 1-63
• Default Address: 63

License

This project is licensed under the MIT License.

Support

For issues and feature requests, please contact the maintainers or refer to the ERMANGIZER protocol documentation.

Changelog

v1.0.0

• Initial release
• Support for all ERMANGIZER Modbus registers
• Multiple input format support
• CRC verification
• Comprehensive error handling