UNI-T UT306S/UT306C Infrared Thermometer User Manual

Overview

The UT306S/UT306C infrared thermometer (hereinafter referred to as the thermometer) can quickly and accurately determine the surface temperature of a target by measuring the infrared energy radiated by the target surface. It is suitable for non-contact temperature measurement and features a Distance to Spot (D:S) ratio of 12:1.

Safety Instructions

⚠️ Warning:

In order to prevent eye damage or personal injury, please read the following safety instructions before using the product:

• Do not point the laser directly at persons or animals or indirectly through reflective surfaces.
• Do not look directly at the laser or with optical tools (binoculars, microscopes, etc.).

LASER RADIATION
DO NOT STARE INTO BEAM
CLASS 2 LASER PRODUCT
λ=630-670nm, <1mW, EN60825-1:2014

Cautions:

• If the laser irradiates the user's eyes, please close the eyes immediately and turn the head away.
• Do not disassemble or refit the product and laser without permission.
• To ensure its safety and accuracy, this product should only be repaired by professional maintenance personnel using original replacement parts.
• Replace the batteries when the low battery indicator shows to prevent incorrect measurements.
• Please check the product before using it. If it is damaged, cracked on the surface or missing plastic parts, do not use it.
• Please refer to the emissivity information for the actual temperature. Highly reflective objects or transparent materials will make the actual temperature higher than the measured temperature. When measuring these objects, pay attention to the risk of burns.
• Do not use the product in an environment with flammable and explosive liquid, gas or dust.
• Do not use the product around the environment with steam, dust, or large temperature fluctuations. It may bring inaccurate results and risks.
• Put the product in the current environment for more than 30 minutes before using it to ensure measurement accuracy.
• Do not leave the thermometer on or near objects of high temperature.

Technical Indexes

Characteristics

• With single point laser, making the measurement indication area more accurate.
• Bright, easy-to-read and high-contrast color EBTN display.
• MAX/MIN/AVG/DIF hold.
• With buzzer sound alarm, can quickly find abnormalities.
• Trigger lock, suitable for processes that require temperature monitoring.
• Short press the [Trigger] button in shutdown mode to take a measurement.

Appearance

1. Laser [Laser pointer]

2. Infrared receiving window

3. Trigger [Trigger button]

4. Battery door

5. LCD display

6. LOCK button [Lock measurement button]

7. MODE button [Mode selection button]

8. LASER button [Laser activation button]

9. Laser warning label

LCD Indicators

• Trigger lock [Trigger lock indicator]
• Buzzer [Buzzer indicator]
• HOLD Temperature hold
• Low battery [Low battery indicator]
• ε Emissivity
• MAX MIN AVG DIF Measurement mode
• HI LO Temperature alarm
• SCAN Temperature measurement
• °C/°F Temperature unit
• Temperature main display
• Temperature secondary display

Operating Instructions

Startup

Short press (less than 0.5s) the trigger to turn on the thermometer, and the measured value before the last shutdown will be displayed. Pressing the MODE button can view MAX/MIN/AVG/DIF.

Shutdown

The thermometer will automatically shut down after 15 seconds without any operation in the HOLD mode, and save the current measured value.

Manual Measurement

1. After aiming at the measured object, press the trigger and hold it. When the SCAN symbol is flashing, it means that the temperature is being measured, and the measurement result will be updated on the LCD.
2. Release the trigger, the SCAN symbol will disappear while the HOLD symbol will be displayed. The thermometer will stop measuring the temperature and keep the last measured value.

Lock Measurement

1. Short press the LOCK button to enter the lock measurement mode. The [LOCK] symbol will be displayed on the LCD and the SCAN symbol will flash. The thermometer will measure the target temperature continuously without pressing the trigger all the time.
2. Press the trigger or short press the LOCK button again, the [LOCK] and SCAN symbols will disappear while the HOLD symbol will appear. The thermometer will stop measuring and keep the last measured temperature.
3. Short press the LOCK button in the shutdown state to wake up the thermometer and enter the lock measurement mode.
4. If the LOCK button is pressed and not released for more than 3 seconds, it will be regarded as a misoperation.

MAX/MIN/AVG/DIF Value

Short press the "MODE" button to switch among "MAX MIN AVG DIF" measurement modes in sequence, and the temperature of the corresponding mode will be displayed in the secondary display position.

Laser Indicator

Pressing the LASER button can turn on/off the laser indication function. When it is turned on, the laser symbol will show on the LCD, and the laser will accurately indicate the measured position. Please follow the cautions when turning on the laser to avoid eyes injury.

High and Low Temperature Alarm

If the measured temperature is higher than the set high alarm limit, the HI symbol on the display will flash. If the sound alarm is turned on, the buzzer will beep. If the measured temperature is lower than the set low alarm limit, the LO symbol will flash. If the sound alarm is turned on, the buzzer will beep. If the measured temperature value is within the range of high and low alarm limit, the HI/LO symbol will not show on the display.

Function Settings

In the HOLD interface, long press the "MODE" button for more than 2s to enter the high alarm limit → low alarm limit → emissivity → temperature unit → sound alarm and other function settings. Under these setting interfaces, the user can return to the HOLD interface by pressing the trigger or no operation for 10s.

High Alarm Limit Setting

In the HOLD interface, long press the "MODE" button to enter the high alarm limit setting interface. The user can use [Up Arrow] or [Down Arrow] to adjust. Short pressing will add or subtract 1 to the value each time, and long pressing will add or subtract 10 each second.

Low Alarm Limit Setting

In the HOLD interface, long press and then short press the "MODE" button once to enter the low alarm limit setting interface. The user can use [Up Arrow] or [Down Arrow] to adjust. Short pressing will add or subtract 1 to the value each time, and long pressing will add or subtract 10 each second.

Emissivity Setting

In the HOLD interface, long press the "MODE" button once and then short press the "MODE" button twice to enter the emissivity setting interface. The user can use [Up Arrow] or [Down Arrow] to adjust. Short pressing will add or subtract 0.01 to the value each time, and long pressing will add or subtract 0.1 each second.

Temperature Unit Setting

In the HOLD interface, long press the "MODE" button once and then short press the "MODE" button three times to enter the temperature unit setting interface. The user can use [Up Arrow] or [Down Arrow] to convert the unit °C/°F.

Sound Alarm Setting

In the HOLD interface, long press the "MODE" button once and then short press the "MODE" button four times to enter the sound alarm setting interface. The user can use [Down Arrow] or [Up Arrow] to turn on/off this function.

D: S (Distance to Spot Ratio)

As the distance (D) between the thermometer and the measured target increases, the light spot diameter (S) of the measured area also increases. The relationship between measurement distance and light spot diameter is shown in the figure below.

Spot Size @ Distance D:S= 12:1

Diagram showing Spot Size at different distances for a D:S ratio of 12:1. It illustrates how the spot diameter (S) increases with distance (D). Examples include: 25mm spot at 300mm distance, 50mm spot at 600mm distance, 100mm spot at 1200mm distance. A note states 'The light spot diameter represents 95% of the energy in the circle'.

Field of View

When measuring, make sure that the measured target is larger than the light spot diameter. The smaller the target, the closer the test distance should be (refer to D: S for the detailed light spot diameter). It is recommended that the measured target be larger than twice the light spot diameter of the thermometer.

Diagram illustrating Field of View for infrared thermometers. It shows that the measured target should be larger than the light spot diameter (S). Three scenarios are depicted: 'Bad' (target < S), 'So-So' (target ≈ S), and 'Good' (target > S). The text emphasizes that the target should ideally be larger than twice the spot diameter for accurate measurement.

Emissivity

Emissivity represents the material energy radiation. The emissivity of most organic materials, painted or oxidized surfaces is about 0.95. The user can use masking tapes or flat paints to cover the metal surface, use the high emissivity setting, and then wait for a period of time to make the surface temperatures of the tapes/flat paints and the covered object the same. At this point, the surface temperature of the tapes /flat paints is equal to the metal surface temperature. The following table shows the total emissivity ε of some metals and non-metals.

Maintenance

Cleaning

Blow away the fallen particles with clean compressed air, carefully wipe the lens surface with a moist swab, and clean the shell with a moist sponge or soft cloth. Be careful not to rinse with water or immerse it in water.

Replace Batteries

Install or replace two 1.5V batteries according to the following steps:

1. Remove the battery door.
2. Install the batteries (pay attention to the polarity).
3. Close the battery door.

Troubleshooting