UNI-T UT383S Digital Light Meter Instruction Manual

1. Introduction

The UNI-T UT383S is a compact and precise digital light meter designed for measuring illuminance in Lux (lx) or Foot-Candles (FC). It features a split probe for flexible measurements, auto-ranging capabilities, and data hold functions, making it suitable for various applications including public settings, light manufacturing, photo studios, interior renovation, construction, and greenhouses.

Image 1: The UNI-T UT383S Digital Light Meter, showing the main unit with LCD display and the separate light sensor probe connected by a coiled cable.

2. Safety Information

Please read and understand all safety warnings and operating instructions before using this device. Failure to do so may result in injury or damage to the meter.

• Do not operate the meter in environments with high temperature or humidity.
• Avoid strong vibrations or impacts to the device.
• Keep the light sensor clean and free from obstructions to ensure accurate readings.
• Replace batteries promptly when the low battery indicator appears.

3. Package Contents

The standard package for the UT383S Digital Light Meter includes:

• 1 x UNI-T UT383S Digital Light Meter
• 1 x 1.5V AAA Battery (included)
• 1 x English User Manual

4. Device Layout

The UT383S consists of a main display unit and a separate light sensor probe connected by a coiled cable. The main unit features an LCD display and several control buttons.

Image 2: A detailed view of the UT383S main unit, highlighting the LCD screen and the arrangement of its function buttons.

4.1. Control Buttons:

• Power Button (⏻): Turns the device On/Off.
• MODE Button: Cycles through measurement modes or settings.
• LUX/FC Button: Toggles between Lux and Foot-Candle units.
• HOLD/BL Button: Freezes the current reading on the display. Long press activates/deactivates backlight.
• MAX/MIN Button: Displays maximum or minimum recorded values.

5. Battery Installation

The UT383S requires 1 Lithium Metal battery (included). To install or replace the battery:

1. Ensure the device is powered off.
2. Locate the battery compartment on the back of the meter.
3. Open the battery compartment cover.
4. Insert the battery, observing the correct polarity (+/-).
5. Close the battery compartment cover securely.

6. Operating Instructions

6.1. Power On/Off

• To turn on the meter, press the ⏻ Power button.
• To turn off the meter, press and hold the ⏻ Power button until the display turns off.

6.2. Unit Selection (Lux/FC)

The UT383S can display readings in either Lux (lx) or Foot-Candles (FC).

• Press the LUX/FC button to toggle between Lux and Foot-Candle units. The selected unit will be indicated on the LCD display.

6.3. Data Hold Function

To freeze the current reading on the display:

• Press the HOLD/BL button once. The "HOLD" indicator will appear on the screen.
• Press the HOLD/BL button again to release the hold and resume live measurements.

6.4. Maximum/Minimum Measurement

The meter can record and display the maximum and minimum illuminance values measured during a session.

• Press the MAX/MIN button once to display the maximum recorded value ("MAX" indicator).
• Press the MAX/MIN button a second time to display the minimum recorded value ("MIN" indicator).
• Press the MAX/MIN button a third time to exit MAX/MIN mode and return to live measurement.

6.5. Backlight

For measurements in low-light conditions, the display backlight can be activated.

• Press and hold the HOLD/BL button to turn the backlight on or off.

6.6. Auto Power Off

The meter features an auto power-off function to conserve battery life. It will automatically shut down after a period of inactivity.

• To disable auto power-off, refer to the full user manual for advanced settings.

6.7. Example Application

Image 3: The UT383S in use, demonstrating its application in measuring light intensity within a specialized setup.

7. Video Demonstration

Watch this video for a visual guide on operating a similar UNI-T digital light meter. While the model shown is UT381, the basic functions and button operations are largely similar to the UT383S.

8. Specifications

9. Maintenance

To ensure the longevity and accuracy of your UNI-T UT383S Digital Light Meter, follow these maintenance guidelines:

• Cleaning: Wipe the device and sensor with a soft, dry cloth. Do not use abrasive cleaners or solvents.
• Storage: Store the meter in a cool, dry place away from direct sunlight and extreme temperatures. If storing for extended periods, remove the battery to prevent leakage.
• Sensor Care: Keep the light sensor dome clean and free from dust or fingerprints, as this can affect measurement accuracy.

10. Troubleshooting

If you encounter issues with your UT383S, refer to the following common problems and solutions:

• No Display/Device Not Turning On:
  • Check if the battery is correctly installed with proper polarity.
  • Replace the battery with a new one if it is depleted.
• "OL" (Overload) Display:
  • The measured illuminance exceeds the meter's maximum range. Move the sensor to an area with lower light intensity.
• Inaccurate Readings:
  • Ensure the light sensor is clean and unobstructed.
  • Verify that the correct unit (Lux or FC) is selected for your application.
  • Allow the meter to stabilize in the measurement environment for a few moments.
• Low Battery Indicator:
  • The battery icon on the display indicates low battery. Replace the battery immediately to ensure accurate operation.