Introduction
This Benetech GM321 Infrared Thermometer Gun is a non-contact digital laser temperature gun designed for various applications such as kitchen cooking, food preparation, grilling, pizza ovens, and candy making. It offers high accuracy and a wide temperature measurement range from -58°F to 752°F (-50°C to 400°C). The device features multi-functional capabilities including ambient temperature measurement, maximum/minimum temperature tracking, and adjustable emissivity for precise readings.
Figure 1: Benetech GM321 Infrared Thermometer Gun and included AAA batteries.
Setup
1. Battery Installation
The Benetech GM321 requires two AAA batteries (included). To install the batteries:
- Locate the battery compartment cover on the handle of the thermometer.
- Gently pull down the battery cover to open the compartment.
- Insert two AAA batteries, ensuring correct polarity (+/-) as indicated inside the compartment.
- Close the battery cover securely until it clicks into place.
Figure 2: Battery installation for the GM321 thermometer.
2. Initial Power On
Once batteries are installed, the device is ready for use. Simply press the trigger to power on the thermometer and begin measuring.
Video 1: Demonstration of how to use the Benetech Infrared Thermometer, including battery installation and basic operation.
Operating Instructions
1. Basic Temperature Measurement
To measure the surface temperature of an object:
- Point the infrared thermometer at the target object.
- Press and hold the trigger. The laser pointer will activate, indicating the measurement area.
- The temperature reading will be displayed instantly on the LCD screen. Release the trigger to hold the reading.
Figure 3: Measuring temperature of food on a grill using the thermometer gun.
2. Unit Conversion (°C/°F)
To switch between Celsius (°C) and Fahrenheit (°F):
- With the device powered on, press the °C/°F button located below the display.
- The unit on the display will change accordingly.
3. Mode Selection (MAX/MIN/Ambient/Emissivity)
The thermometer offers multiple measurement modes. Press the MODE button to cycle through them:
- HOLD: Data Hold (default after releasing trigger).
- MAX: Displays the maximum temperature recorded during continuous measurement.
- MIN: Displays the minimum temperature recorded during continuous measurement.
- AT: Measures the current ambient temperature.
- EMS: Emissivity adjustment mode.
- CAL: Self-calibration mode.
Figure 4: Multi-functional display of the thermometer.
Figure 5: Measuring maximum and minimum temperatures in an oven.
4. Emissivity Adjustment
Emissivity (EMS) is crucial for accurate temperature measurement of different surfaces. The GM321 allows adjustment from 0.1 to 1.0, with a default of 0.95. To adjust emissivity:
- Press the MODE button until "EMS" appears on the display.
- Use the Up (▲) and Down (▼) buttons to adjust the emissivity value.
- Refer to the table below for common material emissivity values.
Figure 6: Emissivity adjustment and common material values.
5. Distance to Spot Ratio (D:S)
The GM321 has a Distance to Spot (D:S) ratio of 12:1. This means that at a distance of 12 inches, the measurement spot size will be 1 inch. To ensure accurate readings, measure from a distance where the target object completely fills the spot size.
Figure 7: Understanding the Distance to Spot Ratio.
Maintenance
1. Cleaning
To clean the thermometer, gently wipe the surface with a soft, damp cloth. Do not use abrasive cleaners or immerse the device in water.
2. Battery Replacement
When the low battery indicator appears on the display, replace the two AAA batteries following the installation steps in the Setup section.
Troubleshooting
1. Inaccurate Readings
- Emissivity: Ensure the emissivity setting is correctly adjusted for the material being measured. Refer to the Emissivity Adjustment section.
- Distance: Maintain the correct distance to spot ratio. Ensure the target completely fills the measurement spot.
- Interference: Avoid measuring through steam, dust, or highly reflective surfaces. These can significantly affect accuracy.
Figure 8: Avoid steam and dust for accurate readings.
2. Self-Calibration
The device supports self-calibration between -1.5°C and +1.5°C to fine-tune accuracy. Access the CAL mode via the MODE button and use the Up/Down arrows to adjust.
Specifications
| Feature | Detail |
|---|---|
| Temperature Range | -58°F to 752°F (-50°C to 400°C) |
| Accuracy | ±1.5% |
| Response Time | 0.5 seconds |
| Distance to Spot Ratio (D:S) | 12:1 |
| Emissivity | Adjustable from 0.1-1.0 (Default 0.95) |
| Auto Power-off | Yes (20 seconds) |
| Dimensions | 5.69 x 1.5 x 3.66 inches |
| Weight | 4.8 ounces |
| Power Source | 2 AAA batteries (included) |
| Included Components | 1x infrared thermometer |
Important Safety Information
- NOT FOR HUMAN USE: This infrared thermometer is designed for industrial and scientific applications, as well as for measuring surface temperatures of food, oil, and water. It is not intended for measuring human body temperature.
- LASER SAFETY: Do not stare directly into the laser beam. Avoid pointing the laser at people or animals.
- AVOID INTERFERENCE: Steam and dust can interfere with the accuracy of infrared thermometers. Ensure a clear line of sight to the target surface.
Figure 9: Important safety guidelines for thermometer usage.
Warranty & Support
Benetech provides lifetime after-sales service for this product, including one year of quality assurance. For any questions or support, please contact our 7/24 customer service team.
For further assistance, please visit the official Benetech Store: Benetech Store on Amazon
