1. Introduction
The ANENG RN02 Digital Inclinometer is a versatile and precise tool designed for accurate angle and slope measurements. Featuring a strong magnetic base, smart auto-flip screen, and USB-C fast charging, it is ideal for a wide range of applications including construction, woodworking, industrial maintenance, and precision instrument research. This manual provides detailed instructions for the proper use, calibration, and maintenance of your device.

Figure 1.1: ANENG RN02 Digital Inclinometer Overview
2. Product Overview
2.1 Key Features
- Strong Magnetic Base: Equipped with a powerful four-sided magnetic design for firm adsorption on metal surfaces, allowing for hands-free operation.
- Smart Auto-Flip Screen: The LCD backlit display automatically flips to ensure clear and easy-to-read data from any orientation.
- Type-C Fast Charging: Built-in 3.7V 350mAh lithium battery, rechargeable via Type-C data cable connected to a DC 5V output adapter.
- Versatile Measurement Modes: Supports angle/slope measurement, relative/absolute measurement, horizontal, vertical, and gradient detection.
- High Accuracy: Offers an angular resolution of 0.05° and an angular error range of ±0.5°.
- Data Retention: Long press function to hold the displayed measurement.
- Auto Power Off: Automatically shuts down after 12 minutes of no operation to conserve battery.
- Anti-skid Design: Features anti-slip concave-convex groove design for secure handling.
2.2 Components and Controls

Figure 2.1: Product Components
- Charging Port (USB-C): For connecting the Type-C data cable to charge the device.
- LCD Backlit Display: Shows measurement values, battery status, and mode indicators.
- Power Button: Long press to power the device on or shut it down.
- H/% Button (Lock/Slope Key): Single press to switch between angle and slope percentage. Long press for data retention (HOLD function).
- ZERO Button: Short press to set the current position as the relative zero point. Short press again to restore to absolute measurement.
3. Specifications

Figure 3.1: Function Parameter Index
| Measurement Function | Resolution | Accuracy |
|---|---|---|
| Inclination Angle | 0.05° | ±(0.5° + 5 words) |
| Tilt Ratio | 0.05% | ±(0.1% + 10 words) |
| Relative Value Measurement | ✔️ | |
| Four-sided Magnetic Attraction | ✔️ | |
| LCD Backlit Screen | ✔️ | |
| Automatic Screen Flip | ✔️ | |
| Data Retention | ✔️ | |
| Calibration Function | ✔️ | |
| Auto Power Off | After 12 minutes of no operation | |
| Lithium Battery Type | 3.7V 350mAh | |
| Material | ABS | |
| Weight | 90g |
4. Setup
4.1 Charging the Device
The ANENG RN02 is equipped with a built-in 3.7V 350mAh lithium battery. To charge the device:
- Locate the USB-C charging port on the side of the inclinometer.
- Connect the provided Type-C data cable to the charging port.
- Connect the other end of the cable to a DC 5V output adapter (not included).
- During charging, a bright red indicator light will be on.
- Once fully charged, the indicator light will turn off (extinction).

Figure 4.1: Type-C Charging Indicator
4.2 Power On/Off
To power on the device, long press the Power Button (3). To power off, long press the Power Button again.
5. Operation
5.1 Basic Measurement
The inclinometer can measure angles in various orientations:
- Horizontal Detection: A value of 0.00° indicates a horizontal state.
- Verticality Detection: A value of 90.00° indicates a vertical state.
- Gradient Detection: Can detect tilt gradients, for example, 45.00°.

Figure 5.1: Horizontal, Vertical, and Slope Detection
5.2 Absolute and Relative Measurement
The device supports both absolute and relative measurement modes:
- Absolute Measurement: This is the default mode, measuring angles relative to true horizontal.
- Relative Measurement: To set a custom datum (zero point), place the inclinometer on the desired surface and short press the ZERO Button (5). The display will show 0.00°, and subsequent measurements will be relative to this new zero point.
- Restore Absolute Measurement: To return to absolute measurement, short press the ZERO Button (5) again.

Figure 5.2: Absolute/Relative Measurement
5.3 Unit Switching (Angle/Slope Percentage)
To switch between angle (°) and slope percentage (%), single press the H/% Button (4).
5.4 Data Retention (HOLD Function)
To hold the current measurement on the screen, long press the H/% Button (4). Long press it again to release the hold function and resume live measurement.
5.5 Automatic Screen Flip
The display automatically rotates 180° when the device is inverted, ensuring the readings are always upright and easy to read.

Figure 5.3: Automatic Screen Flip
6. Calibration
The instrument's accuracy can be affected by impact or temperature changes. Recalibration is recommended to ensure precise and correct measurement results. Follow these steps carefully:

Figure 6.1: Calibration Steps (Part 1)

Figure 6.2: Calibration Steps (Part 2)
- Step 1 (CA.1): Turn on the instrument. Place it on a flat, horizontal surface. Long press the Power Button and the H/% Button simultaneously until the screen displays "CA.1".
- Step 2 (CA.2): When "1" in "CA.1" starts to flicker and beep, rotate the instrument 180° (keeping it flat on the surface) and lay it flat again. Press the H/% Button to confirm. The screen will then display "CA.2".
- Step 3 (CA.3): When "2" in "CA.2" starts to flicker and beep, rotate the instrument 90° (keeping it flat on the surface) and lay it flat again. Press the H/% Button to confirm. The screen will then display "CA.3".
- Step 4 (CA.4): When "3" in "CA.3" starts to flicker and beep, rotate the instrument 180° (keeping it flat on the surface) and lay it flat again. Press the H/% Button to confirm. The screen will then display "CA.4".
- Step 5 (CA.5): When "4" flashes and buzzes, press the H/% Button to display "CA.5". Place the instrument with its display screen horizontally facing down on the edge of a plane, ensuring the button is suspended (not touching the surface).
- Step 6 (CA.6): When "5" flashes and buzzes, turn the instrument 180° (as shown in the figure) until the display screen is upwards and flat. Press the H/% Button to confirm. The screen will then display "CA.6".
- Step 7 (CAd): Wait until "6" in "CA.6" flashes. Press the H/% Button. The screen will display "CAd". After approximately 3 seconds, the instrument calibration is completed, and it will enter normal measurement mode.
7. Maintenance
- Cleaning: Use a soft, dry cloth to clean the device. Do not use abrasive cleaners or solvents.
- Storage: Store the inclinometer in a dry place, away from direct sunlight and extreme temperatures.
- Battery Care: Charge the device regularly, even if not in frequent use, to maintain battery health. Avoid fully discharging the battery for extended periods.
- Avoid Impact: Protect the device from drops and impacts, as this can affect its accuracy and functionality.
8. Troubleshooting
- Device not turning on: Ensure the battery is charged. Connect to a power source using the USB-C cable.
- Inaccurate readings: Perform a calibration as described in Section 6. Ensure the measurement surface is clean and stable.
- Screen not flipping automatically: Check for any physical obstructions. If the issue persists after recalibration, contact support.
- Buttons unresponsive: Ensure the device is not in a locked state (if applicable, though RN02 uses long press for hold). Try powering off and on again.
9. User Tips
- For best magnetic adhesion, ensure the metal surface is clean and free of debris.
- Regularly check the battery level, especially before critical tasks, to avoid interruptions.
- When measuring, try to keep the inclinometer stable on the surface to get the most accurate reading.
- Utilize the relative measurement function for quick comparisons between two surfaces or to establish a temporary zero point.
10. Safety Information
- Do not expose the device to water or excessive moisture.
- Avoid operating the device in environments with extreme temperatures or high humidity.
- Keep the device out of reach of children.
- Do not attempt to disassemble or modify the device, as this will void the warranty and may cause damage or injury.
- Dispose of the battery and device according to local regulations.
11. Package Contents

Figure 11.1: Package Contents
The ANENG RN02 Digital Inclinometer package includes:
- Digital Inclinometer (RN02) x1
- Type-C Charging Cable x1
- User Manual x1
- Package Box x1
12. Product Demonstration Video
Video 12.1: ANENG RN02 Digital Inclinometer in action, demonstrating its features and use cases.





