Eventek ET300
Eventek Infrared Thermometer Gun User Manual
Model: ET300
Introduction
This manual provides detailed instructions for the safe and effective operation of your Eventek Infrared Thermometer Gun, Model ET300. This device is designed for non-contact temperature measurement of surfaces, liquids, and equipment across a wide range of applications, including cooking, automotive diagnostics, and HVAC. It offers rapid, accurate readings with adjustable emissivity for various materials.
Please read this manual thoroughly before use and retain it for future reference. Adherence to these instructions will ensure optimal performance and longevity of your thermometer.
Product Features
- Lightning-Fast Precision: Obtain temperature readings in just 0.5 seconds with an accuracy of ±1.5% across a range of -58°F to 932°F (-50°C to 500°C).
- Optimal Distance-to-Spot Ratio: A 12:1 D:S ratio allows for safe and accurate measurement of targets from a distance.
- Adjustable Emissivity: Features adjustable emissivity from 0.1 to 1.0, making it suitable for measuring various surfaces including metal, ceramic, plastic, and glass.
- Smart Operation: Easily switch between °F and °C. Includes MAX/MIN memory functions to track temperature extremes.
- Energy Saving: Equipped with a 20-second auto shut-off feature and a low-battery indicator to conserve power.
- Durable Design: Built for reliability and precision, suitable for both professional and DIY use.
Package Contents
Upon opening the package, please verify that all items listed below are present and in good condition:
- 1 x Eventek Infrared Thermometer Gun (Model ET300)
- 2 x AAA Batteries
- 1 x User Manual

Figure 1: Eventek Infrared Thermometer Gun and included AAA batteries.
Setup
Battery Installation
- Locate the battery compartment cover on the handle of the thermometer.
- Slide the cover open in the direction indicated by the arrow.
- Insert the two AAA batteries, ensuring correct polarity (+ and -) as marked inside the compartment.
- Close the battery compartment cover securely until it clicks into place.
Initial Power-On
Once batteries are installed, the device is ready for use. Press the trigger to power on the thermometer. The LCD display will illuminate.
Operating Instructions
Taking a Measurement
- Point the thermometer's laser at the target surface you wish to measure.
- Press and hold the trigger. The laser will activate, indicating the measurement area.
- The temperature reading will appear on the LCD display almost instantly (within 0.5 seconds).
- Release the trigger to hold the reading on the display. The device will automatically shut off after 20 seconds of inactivity to conserve battery life.

Figure 2: Non-contact temperature measurement in action, highlighting the 12:1 distance-to-spot ratio.
Switching Temperature Units (°F/°C)
To switch between Fahrenheit (°F) and Celsius (°C), press the °C/°F button located below the display. The selected unit will be indicated on the LCD.
MAX/MIN Temperature Modes
Press the "MODE" button to cycle through different display modes, including Maximum (MAX) and Minimum (MIN) temperature readings during a continuous scan. This allows you to track temperature extremes within a scanned area.

Figure 3: Using MAX/MIN modes to identify temperature variations, such as in a pool.
Adjusting Emissivity (EMS)
Emissivity is the ability of a surface to emit energy by radiation. Different materials have different emissivities. For accurate readings, adjust the emissivity setting (EMS) on your thermometer to match the material being measured. The adjustable range is 0.1 to 1.0.
Consult a standard emissivity table for common materials if precise adjustment is required. For general use, the default setting is often sufficient for many non-reflective surfaces.

Figure 4: Demonstrating adjustable emissivity for accurate temperature measurement on various materials.
Important Safety Note: Not for Human Use
This industrial-grade thermometer is designed exclusively for measuring the temperature of objects, surfaces, and liquids. It is NOT intended for medical use or for measuring human body temperature. Using it for this purpose may result in inaccurate readings and should be avoided.

Figure 5: This thermometer is for object temperature measurement only, not for human body temperature.
Maintenance
Cleaning
To clean the thermometer, wipe the surface with a soft, damp cloth. Do not use abrasive cleaners or immerse the device in water. Ensure the lens is clean and free of dust or debris for accurate readings.
Battery Replacement
When the low battery indicator appears on the display, replace the AAA batteries as described in the "Battery Installation" section. Always use fresh AAA batteries.
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 to prevent leakage.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No display/Device won't turn on | Dead or incorrectly installed batteries. | Check battery polarity or replace with new AAA batteries. |
| Inaccurate readings | Incorrect emissivity setting; dirty lens; target too far/too close; ambient temperature fluctuations. | Adjust emissivity; clean the lens; ensure proper distance (12:1 D:S ratio); allow device to acclimate to ambient temperature. |
| Laser not visible | Laser function disabled; bright ambient light. | Check if the laser is enabled via the mode button; use in less bright conditions if possible. |
Specifications
| Feature | Detail |
|---|---|
| Model Number | ET300 |
| Temperature Range | -58°F to 932°F (-50°C to 500°C) |
| Accuracy | ±1.5% or ±1.5°C/34.7°F |
| Distance-to-Spot Ratio | 12:1 |
| Response Time | 0.5 seconds |
| Emissivity | Adjustable 0.1-1.0 |
| Power Source | 2 x AAA Batteries (included) |
| Auto Shut-off | 20 seconds |
| Display Type | LED Backlit |
| Outer Material | Plastic |
| Dimensions | 6.57 x 3.62 x 1.85 inches |
| Weight | 5.61 ounces |
Warranty and Support
Your Eventek Infrared Thermometer Gun is backed by a 2-year warranty from the date of purchase, covering defects in materials and workmanship under normal use. This warranty does not cover damage caused by misuse, accident, unauthorized modification, or neglect.
For technical assistance, warranty claims, or any questions regarding your product, please contact Eventek customer support. Our team is available 24/7 to provide assistance.
Please retain your proof of purchase for warranty service.
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