1. Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of the Eletechsup N4CID08 8-channel 4-20mA/0-20mA Current Sensor Converter. This module is designed for analog current collection via RS485 using the MODBUS RTU protocol, making it suitable for PLC and remote IO expansion applications. It is available in 5V, 12V, and 24V versions.
2. Key Features
- Working Voltage: DC5V or DC 7-24V (two versions available)
- Working Current: Standby 6-7mA, operating 11-20mA
- Protocol Support: Standard Modbus RTU commands (function codes: write 06/16, read 03/04)
- Hardware Protection: Hardware reset function, RS485 with TVS anti-surge protection, anti-reverse power supply
- Parallel Operation: Up to 64 devices can be used in parallel in MODBUS command mode
- Baud Rate: Default 9600BPS (selectable: 1200, 2400, 4800, 19200, 38400, 57600, 115200BPS)
- Check Mode: No check, even check, and odd check options
- Data Return Time: Configurable data sending return time, maximum 1000ms
- Compact Design: 2.54MM pin header version, fully compatible with terminal block versions (e.g., N4AIA08), designed for minimal size for use as a core board or embedded into a base board.
3. Technical Specifications
| Attribute | Value |
|---|---|
| Model Number | N4CID08 |
| Type | Module |
| Brand Name | eletechsup |
| Working Voltage | DC5V / DC 7-24V |
| Working Current (Standby) | 6-7mA |
| Working Current (Operating) | 11-20mA |
| Modbus RTU Function Codes | Write 06/16, Read 03/04 |
| Max Parallel Devices | 64 |
| Default Baud Rate | 9600BPS |
| Selectable Baud Rates | 1200, 2400, 4800, 19200, 38400, 57600, 115200BPS |
| Check Mode Options | No check, Even check, Odd check |
| Max Data Sending Return Time | 1000ms |
| Dimensions (only board) | 42 * 17.8 * 5mm |
| Dimensions (with pin) | 42 * 17.8 * 11mm |
| Weight (only board) | 4 grams |
| Weight (with pin) | 4.6 grams |
| Package Length | 12 cm |
| Package Width | 10 cm |
| Package Height | 4 cm |
| Package Weight | 0.001 kg |
| Origin | Mainland China |
| Condition | New |
| Customization | Yes |
4. Package Contents
The package includes:
- 1 x DC 5V 12V-24V 8 Channels 4-20MA to RS485 Converter Module
5. Interface Definition
The module features the following pin definitions:
- VIN: Power input +
- GND: Power input -
- I1-I8: Current input channels 1 through 8
- A+: RS485 signal A+
- B-: RS485 signal B-
6. Setup and Installation
6.1. Initial Inspection
Before first use, inspect the product for any damage. Do not use if damaged. Remove any protective films from the device.
6.2. Wiring the Module
Connect the power supply and current sensors according to the diagrams below. Ensure correct polarity for power input (VIN and GND) and proper connection for RS485 signals (A+ and B-).
6.3. System Connection
The module can be integrated into a larger system involving a PC, USB to RS485 converter, PLC, and HMI, as shown in the system connection diagram.
7. Operation
7.1. Modbus Communication
The N4CID08 module communicates using the standard Modbus RTU protocol. You can use Modbus Poll software or similar tools to interact with the module. The module supports function codes 06/16 for writing and 03/04 for reading data.
Refer to the official user manual PDF for detailed Modbus register addresses and commands:
7.2. Modbus Poll Software Demonstration
The following video demonstrates how to use Modbus Poll software to connect to the module and write single registers, illustrating how to configure and interact with the device.
7.3. Factory Reset
To perform a factory reset, short the RES jumper for 5 seconds. This will restore the module to its default settings, including the default baud rate of 9600BPS.
8. Maintenance
To ensure the longevity and optimal performance of your N4CID08 module:
- Store the module in a dry place when not in use.
- Keep it away from children unless supervised by an adult.
- Avoid exposing the module to water or excessive moisture.
- Handle with care to prevent physical damage.
- Regularly check connections for secure fit and absence of corrosion.
9. Troubleshooting
9.1. Current Reading Deviation
If the current reading deviation is greater than 3%, this value can be corrected. The Modbus register allows for adjustment:
- A value of 1000 means a 1:1 increase (no change).
- A value of 1010 means a 1% increase.
- A value of 990 means a 1% decrease.
Adjust this register value as needed to calibrate the current readings.
9.2. Communication Issues
- Check Baud Rate: Ensure the baud rate set in your Modbus master matches the module's baud rate. The default is 9600BPS.
- Verify Wiring: Double-check all power and RS485 connections (A+, B-, GND) for correctness and secure contact.
- RS485 Termination: For longer RS485 bus lengths or noisy environments, ensure proper termination resistors are used.
- Power Supply: Confirm the module is receiving the correct voltage (DC5V or DC 7-24V) and sufficient current.
- Factory Reset: If communication issues persist, try performing a factory reset as described in Section 7.3.
10. User Tips
- When embedding the N4CID08 into a custom base board, ensure adequate clearance for the pin headers if using the 'with pin' version.
- For applications requiring precise current measurements, utilize the deviation correction feature to fine-tune accuracy.
- Consider the 'only board' version for space-constrained applications where direct soldering or custom connectors are preferred over pin headers.
11. Safety & Warnings
Important Safety Information
Read all instructions before use. Failure to follow these instructions may result in damage to the product or personal injury.
- Keep the device and its cord out of reach of children under 3 years old.
- Keep away from children unless supervised by an adult.
- Do not use this product for purposes other than its intended use.
- Inspect the product before each use; do not use if damaged.
- Follow installation and operation guidelines to avoid injury.
- Do not expose to water or moisture.
- Handle with care to avoid cuts or injuries.
12. Warranty and Support
For technical support, troubleshooting assistance, or inquiries regarding product functionality, please contact the manufacturer or your vendor. Ensure you have your product model (N4CID08) and any relevant batch/serial numbers available when seeking support.
Manufacturer: Guangzhou Keshen Electronic Technology Co., Ltd
Email: eletechsup@163.com
