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:

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- 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

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- 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

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

Installation

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

Then restart Node-RED.

Usage

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

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The node accepts three input formats:

#### 1. Buffer (Recommended)
`javascript
// From serial port or TCP Modbus connection
msg.payload = buffer; // Raw Buffer object
`

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

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

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#### Detailed Format (Default)
`javascript
{
"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
`javascript
{
"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

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`javascript
// 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
}
`


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`javascript
// 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:

`javascript
{
"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:

1. Install dependencies:
`bash
npm install
`

2. Build the project:
`bash
npm run build
`

3. For development with auto-rebuild:
`bash
npm run dev
`

Troubleshooting

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1. "CRC check failed"
- Verify the Modbus message is complete and uncorrupted
- Check that the entire message including CRC is provided

2. "Message too short"
- Ensure the input contains at least 4 bytes (address + function code + CRC)

3. "Unsupported input type"
- Use one of the supported formats: Buffer, hex string, or number array
- Enable auto-detection if unsure of the format

4. 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

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

1. Add a debug node connected to the ERMANGIZER Modbus node output
2. Set debug to display complete message object
3. 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

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