EM18 RFID Long Range Module

The EM18 RFID Long Range Module is a versatile, contactless RFID reader designed to detect and read 125kHz passive RFID tags quickly and reliably. It is widely used in security, automation, and attendance systems due to its plug-and-play serial interface and fast data transmission.

With a reading distance of up to 12 cm, the EM18 is an excellent choice for embedded electronics, access management, vehicle identification, and IoT-based entry systems. It outputs the unique tag ID via UART or Wiegand interface, making integration easy with Arduino, Raspberry Pi, or other microcontrollers.

Key Features

✅ Operating Frequency: 125kHz RFID reader
✅ Long Range Reading: Detects RFID cards/tags up to 12 cm
✅ Multiple Interfaces: UART (TTL) and Wiegand output supported
✅ Fast Response Time: Less than 100 ms per tag read
✅ Plug and Play: Simple integration with Arduino, Raspberry Pi, or microcontrollers
✅ Compact Design: Lightweight and easy to embed in access systems
✅ Low Power Consumption: Operates efficiently at 5V DC

Technical Specifications

• Model: EM18

• Operating Voltage: 5V DC

• Operating Current: 50 mA (typical)

• Frequency: 125 kHz

• Reading Distance: 8 – 12 cm (depends on tag and environment)

• Output Format: RS232 / UART TTL / Wiegand

• Data Rate: 9600 bps (default)

• Reading Time: <100 ms per tag

• Dimension: 32mm x 32mm x 8mm

• Operating Temperature: -20°C to +60°C

• Supported Tags: 125kHz RFID cards, EM4100/EM4200 compatible

Working Principle

The EM18 RFID module generates a 125kHz electromagnetic field that powers nearby passive RFID tags. Each tag has a unique ID code, which is read by the module and transmitted through UART serial communication to a microcontroller or PC for processing.

This data can then be used to grant access, mark attendance, or trigger automation based on the stored database or programmed logic.

Applications

🔹 Attendance Systems – Identify users through RFID tags or cards.
🔹 Access Control – Ideal for doors, gates, and smart locks.
🔹 IoT Projects – RFID-based automation and logging.
🔹 Vehicle Identification – Parking and security systems.
🔹 Inventory Management – Track items with RFID tags.
🔹 Automation Projects – Integrated with Arduino or Raspberry Pi for smart electronics.

How to Use with Arduino

1. Connect VCC (5V) and GND.

2. Connect TX of EM18 to RX (D0) of Arduino.

3. Open Serial Monitor (9600 baud rate).

4. Scan RFID cards to view their unique IDs.

5. Use these IDs in your Arduino code for access or attendance logic.

For easy setup, you can integrate this module with the Arduino UNO or NodeMCU ESP8266 for wireless RFID systems.

Precautions

⚠️ Avoid exposing the module to strong electromagnetic fields.
⚠️ Keep metallic objects away from the antenna for accurate reading.
⚠️ Ensure power supply stability to avoid data errors.
⚠️ Use genuine 125kHz RFID tags only.

Internal Links

• Sensors & Modules

• Arduino Boards

• Wireless Modules

• RFID Tags & Cards

• NodeMCU WiFi Module

YouTube Tutorial

🎥 Watch: How to Interface EM18 RFID Module with Arduino UNO

Summary

The EM18 RFID Long Range Module is a reliable, low-cost RFID reader that delivers fast, accurate, and secure identification of 125kHz RFID tags. Its serial communication support, plug-and-play design, and compatibility with Arduino and Raspberry Pi make it a top choice for access control, attendance, and IoT automation systems.