Eventek ET300
Eventek ET300 Industrial Infrared Thermometer User Manual
1. Introduction
Thank you for choosing the Eventek ET300 Industrial Infrared Thermometer. This device is designed for non-contact temperature measurement in various industrial and household applications. It provides quick, accurate, and safe temperature readings for surfaces.
IMPORTANT SAFETY WARNING: This thermometer is an industrial-grade instrument and is NOT FOR MEASURING HUMAN BODY TEMPERATURE. Using it for this purpose will result in inaccurate readings.
Please read this manual thoroughly before operating the device to ensure proper use and to prevent potential hazards.

Image 1.1: The Eventek ET300 Infrared Thermometer is designed for industrial use and should not be used to measure human body temperature.
2. Product Overview
The Eventek ET300 features a robust design for durability and ease of use. It includes a clear LCD display, intuitive buttons, and a comfortable grip.

Image 2.1: Front view of the Eventek ET300 Infrared Thermometer, highlighting its design and laser functionality.
2.1. Device Components
- Infrared Sensor: Detects infrared radiation to measure temperature.
- Laser Pointer: Helps to aim at the target measurement area.
- LCD Display: Shows temperature readings, mode indicators, and battery status.
- Measurement Trigger: Activates the measurement and laser.
- Mode Button: Cycles through different functions (e.g., Emissivity, Max/Min).
- °C/°F Button: Switches between Celsius and Fahrenheit units.
- Backlight/Laser Button: Toggles display backlight and laser on/off.
- Battery Compartment: Holds two AAA batteries.
2.2. LCD Display Indicators

Image 2.2: Detailed view of the LCD display and its various indicators.
- HOLD: Data Hold function active.
- SCAN: Currently scanning for temperature.
- CAL: Self-calibration mode.
- EMS: Emissivity setting.
- AT: Ambient Temperature.
- MAX/MIN: Maximum or Minimum temperature reading.
- Laser On Icon: Indicates the laser pointer is active.
- Backlight Icon: Indicates the display backlight is active.
- Low Battery Indicator: Appears when battery power is low.
- °C/°F: Temperature unit indicator.
- Reading: The measured temperature value.
3. Setup
3.1. Battery Installation
The Eventek ET300 requires two AAA batteries (not included) for operation. Ensure correct polarity when installing.
- Locate the battery compartment cover on the handle of the thermometer.
- Open the battery compartment cover.
- Insert two AAA batteries, ensuring the positive (+) and negative (-) terminals match the indicators inside the compartment.
- Close the battery compartment cover securely.

Image 3.1: Illustration of battery installation in the Eventek ET300.
4. Operating Instructions
4.1. Basic Measurement
- Point the thermometer at the target surface.
- Press and hold the measurement trigger. The laser pointer will activate (if enabled) to indicate the measurement spot, and the SCAN icon will appear on the display.
- Release the trigger. The measured temperature will be displayed, and the HOLD icon will appear, indicating the reading is held.
- The device will automatically turn off after approximately 20 seconds of inactivity to conserve battery life.

Image 4.1: Demonstrating how to hold and aim the thermometer for measurement.

Image 4.2: The thermometer provides a quick response time for various applications.
4.2. Distance-to-Spot Ratio (D:S)
The ET300 has a Distance-to-Spot Ratio (D:S) of 12:1. This means that at a distance of 12 units from the target, the measurement spot diameter will be 1 unit. For accurate readings, ensure the target area is larger than the spot size. Measuring closer to the target will result in a smaller measurement spot and more precise readings.

Image 4.3: Understanding the Distance-to-Spot Ratio for accurate measurements.
4.3. Adjusting Emissivity
Emissivity is the ability of a material to emit thermal energy. Different materials have different emissivity values. The ET300 has an adjustable emissivity of 0.8 or 0.95. For most organic materials, painted surfaces, and water, an emissivity of 0.95 is suitable. For shiny metals, a lower emissivity might be required, but this model offers limited adjustment.
- With the device on, press the 'MODE' button until 'EMS' appears on the display.
- Use the up/down buttons (if available, or cycle through 'MODE' if only two options) to select between 0.8 and 0.95.
- Press the measurement trigger to confirm the setting or wait for auto-exit.
4.4. Switching Temperature Units (°C/°F)
To switch between Celsius (°C) and Fahrenheit (°F), simply press the dedicated '°C/°F' button located on the device.
4.5. MAX/MIN Function
While scanning (trigger held), the thermometer can display the maximum or minimum temperature detected during that scan. Press the 'MODE' button to cycle through these options if available.
5. Maintenance
5.1. Cleaning
- Lens Cleaning: The sensor lens is the most delicate part. Clean it with a soft, damp cloth or cotton swab. Do not use abrasive materials or solvents.
- Housing Cleaning: Clean the device housing with a damp cloth and mild soap. Do not immerse the device in water.
5.2. Battery Replacement
When the low battery indicator appears on the display, replace the two AAA batteries as described in the Setup section (3.1). Prompt replacement ensures continued accurate operation.

Image 5.1: The thermometer features a low battery indicator and auto-off function for energy saving.
5.3. Storage
Store the thermometer in a cool, dry place away from direct sunlight and extreme temperatures. Remove batteries if the device will not be used for an extended period.
6. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No display/Device won't turn on | Dead or incorrectly installed batteries. | Replace batteries, ensuring correct polarity. |
| Inaccurate readings | Incorrect emissivity setting; Target too small; Distance too far; Lens dirty. | Adjust emissivity; Ensure target is larger than spot size; Move closer to target; Clean the lens. |
| Laser not working | Laser disabled; Low battery. | Press the Backlight/Laser button to enable; Replace batteries. |
| Display shows 'HI' or 'LO' | Temperature is outside the measurement range. | Ensure the target temperature is within -50°C to 420°C (-58°F to 788°F). |
7. Specifications
| Feature | Specification |
|---|---|
| Model | ET300 |
| Temperature Range | -50°C to 420°C (-58°F to 788°F) |
| Accuracy | ±2% or ±2°C |
| Response Time | <0.5 seconds |
| Distance Spot Ratio (D:S) | 12:1 |
| Emissivity | Adjustable (0.8 / 0.95) |
| Display Type | LED Backlit LCD |
| Power Source | 2 x AAA Batteries (not included) |
| Auto-off | Approx. 20 seconds |
| Material | ABS |
| Dimensions (L x W x H) | 7.48 x 1.81 x 4.49 cm |
| Weight | 160 grams |
| Certifications | CE |
8. Warranty and Support
For any questions, technical support, or warranty inquiries regarding your Eventek ET300 Infrared Thermometer, please contact our customer support team.
Email: support@even-tools.com
Please provide your product model (ET300) and a detailed description of your issue when contacting support for faster assistance.
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