1. Introduction
The KERUI W204 4G Home Alarm Security System is a comprehensive security solution designed to protect your home or business. This system integrates WIFI and GSM/4G connectivity, allowing for remote control via the Tuya Smart app, SMS, and calls. It features a 2.4-inch TFT color screen, touch keyboard, and compatibility with various wireless sensors such as PIR motion detectors, door/window sensors, smoke detectors, and more. The system provides accurate alerts, supports scheduled arm/disarm functions, and includes a backup battery for continuous operation during power outages.

Figure 1: KERUI W204 4G Home Alarm Security System components.
2. Package Contents (KIT 1 Example)
Please verify that all items are present in your package:
- 1x W204 4G GSM/WIFI Tuya Alarm Panel
- 8x P831 PIR Motion Sensor (battery not included)
- 8x D025 Door/Window Sensor (battery not included)
- 4x RC531 Remote Controller
- 1x Wired Siren
- 1x J008 Wireless Siren
- 1x S20 Smoke Detector (battery not included)
- 2x RFID Card
- 1x User Manual
3. Specifications
| Feature | Specification |
|---|---|
| Model Number | W204 (KR-W204) |
| Input Voltage | DC 5V1A |
| Standby Current | <50mA |
| Alarm Current | <450mA |
| Wireless Frequency | 433MHz |
| GSM Standard | Support GSM850/900/1800/1900MHz |
| Back-up Battery | 3.7V High Capacity LI Battery (8 hours standby) |
| Alarm Loudness | 80dB (Built-in Siren) |
| Zone Number | 99 |
| Alarm Type | The Alarm, SMS, Apps Control |
| Output Number | 8 |
| Kit Configuration | Door/Window Sensor (example) |
| Communication Interface | Wireless |
| Arming Type | APP |
| Video Interface | Yes |
| Display | Yes (2.4-inch TFT color screen) |
| Password Keyboard | Yes |
| Smart Home Platform | Tuya |
| Certification | CE |
4. Setup Guide
4.1 Initial Power-Up and SIM Card Installation
- Connect the DC 5V1A power adapter to the alarm panel.
- Locate the ON/OFF switch and SIM card port on the back of the panel.
- Ensure the panel is OFF. Insert a compatible GSM/4G SIM card into the SIM card slot.
- Switch the panel ON.

Figure 2: Rear view of the alarm panel with SIM card port and power connections.
4.2 App Installation and Pairing
The KERUI W204 system works with the Tuya Smart app, allowing for remote control and monitoring.
- Download the 'Tuya Smart' app from your smartphone's app store (iOS or Android).
- Register or log in to your Tuya Smart account.
- On the app, tap 'Add Device' and select 'Security & Video Surveillance' > 'Alarm (Wi-Fi)'.
- Follow the on-screen instructions to connect the alarm panel to your home Wi-Fi network (2.4 GHz only). Ensure the alarm panel's Wi-Fi indicator is blinking rapidly for pairing.
- Once successfully added, the alarm panel will appear in your app.
Video 1: Demonstrates the process of pairing the KERUI W204 alarm panel with the Tuya Smart app and adding accessories.
4.3 Adding Wireless Accessories (Sensors, Remotes)
The system supports up to 99 zones for various wireless sensors.
- On the alarm panel, navigate to the 'Sensors' menu.
- Select 'Add Sensor' or 'Add Remote'.
- Trigger the sensor (e.g., open a door for a door sensor, press a button on the remote, or activate the PIR motion detector). The panel will detect and add the accessory.
- Assign the sensor to a specific zone and configure its type (e.g., normal, home, 24-hour).

Figure 3: Overview of compatible sensors and smart home integration.

Figure 4: Visual examples of the alarm panel and various accessories.
5. Operating Modes
5.1 Arming and Disarming the System
The KERUI W204 offers multiple ways to arm and disarm your security system:
- Via Keypad: Enter your password on the alarm panel's touch keyboard and press the arm/disarm button.
- Via Remote Control: Use the dedicated arm or disarm buttons on the RC531 remote controller.
- Via Tuya Smart App/SMS: Control the system remotely through the app interface or by sending specific SMS commands.
- Via RFID Card: Swipe a programmed RFID card over the RFID reader on the alarm panel to disarm the system.

Figure 5: Different methods to arm and disarm the system.
5.2 Home Arm Mode
The Home Arm mode allows you to arm specific zones while leaving others disarmed, typically for areas where movement is expected (e.g., living room) while securing perimeter zones (e.g., doors and windows).

Figure 6: Arming options including Home Arm mode.
5.3 Scheduled Arm/Disarm
You can program up to 8 groups of scheduled arm/disarm times to automate your security routine, avoiding manual operation.

Figure 7: Example of scheduled arm/disarm functions.
6. Key Features
6.1 Multi-Language Support
The system supports 8 languages: English, German, Italian, Russian, Spanish, French, Portuguese, and Chinese. The language can be selected from the system settings.

Figure 8: Language selection interface on the alarm panel.
6.2 Accurate Alerts and Siren
In case of a security breach, the W204 alarm system will trigger an 80dB alert from its built-in siren and can also activate an external 110dB wired siren to warn neighbors and deter intruders.

Figure 9: System alerting during an intrusion.
6.3 24/7 Monitoring with Backup Battery
The system is equipped with a 3.7V high-capacity Li-ion backup battery, providing up to 8 hours of standby time during power failures, ensuring continuous protection.

Figure 10: Backup battery feature for uninterrupted security.
6.4 Two-Way Audio Communication
The alarm panel can function as a common phone, allowing you to make and receive calls directly from the host, facilitating communication during emergencies or for general use.

Figure 11: Two-way audio communication via the alarm panel.
6.5 Auto-Dialer Function
In the event of a security breach, the system's auto-dialer function will automatically call up to 6 pre-programmed phone numbers, ensuring that emergency contacts are immediately notified.

Figure 12: Auto-dialer function for emergency notifications.
7. Maintenance
7.1 Battery Management
- Main Panel: The main panel has a built-in rechargeable Li-ion battery. Ensure it is regularly charged by keeping the panel connected to power. The battery provides up to 8 hours of standby time.
- Wireless Sensors: Most wireless sensors (PIR, door/window, smoke detectors) are battery-powered. Check the battery status periodically and replace them as needed. Specific battery types are mentioned in the sensor specifications (e.g., P831 PIR uses CR2450, D025 Door/Window Sensor uses 1*23A 12V, S20 Smoke Detector uses 2x AAA).
- Remote Controllers: RC531 remote controllers use CR2032 batteries. Replace when the indicator light dims or range decreases.
7.2 Cleaning
Wipe the alarm panel and sensors with a soft, dry cloth. Avoid using abrasive cleaners or solvents that could damage the surfaces.
8. Troubleshooting
- System not responding: Check power connection and ensure the backup battery is charged. Verify the ON/OFF switch is in the 'ON' position.
- Sensors not triggering alarm: Ensure sensors are properly paired and their batteries are not depleted. Check sensor placement and range.
- No app notifications: Verify the alarm panel is connected to Wi-Fi and has a stable internet connection. Check app notification settings on your smartphone.
- GSM/4G not working: Ensure a valid SIM card is inserted and has sufficient credit/data. Check network signal strength on the panel display.
- False alarms: Ensure PIR motion detectors are not placed near heat sources or in direct sunlight. Adjust sensitivity if available. Check door/window sensors for proper alignment.
9. User Tips
- Wireless Detectors: The motion detectors (PIR) and door/window sensors are indeed wireless and battery-powered. Remember to check and replace their batteries periodically to ensure continuous protection.
- Optimal Sensor Placement: For PIR motion detectors, place them in areas where intruders are likely to cross, avoiding direct sunlight or heat sources that might cause false alarms. For door/window sensors, ensure the two parts are aligned correctly and within the specified gap.
- App Integration: Leverage the Tuya Smart app for convenient remote control, status checks, and receiving instant alerts.
10. Warranty and Support
For warranty information and technical support, please refer to the documentation provided with your purchase or contact the KERUI Global Store directly. Keep your purchase receipt as proof of purchase.