UT12B - Mètre Uni-T - Free user manual and instructions

Product Type	Non-Contact AC Voltage Detector
Brand	Uni-T
Model	UT12B
Voltage Range	90 VAC to 1000 VAC
Detection Method	Non-contact proximity
Indicators	Red LED and audible beep
Safety Rating	CAT IV 1000V
Pollution Degree	2
Operating Temperature	-10 °C to 50 °C
Storage Temperature	10 °C to 50 °C
Humidity	5% (operating)
Altitude	2000 m maximum
Battery Type	2 x 1.5V AAA alkaline
Auto Power Off	After approx. 3 minutes of inactivity
Beeper Mute Function	Yes, toggle via power button
Standards Compliance	EN61010-1, UL61010-1, CASC 22.1 No. 61010-1, CE
Protection Level	Double insulation (Class II)
Material	Plastic housing
Cleaning	Wipe with damp cloth and mild detergent; no abrasives

Frequently Asked Questions - UT12B Uni-T

How does the Uni-T UT12B detect voltage?

The UT12B detects AC voltage by non-contact proximity. Place the probe tip near a conductor; it will beep and flash a red LED when voltage between 90V and 1000V AC is present.

What voltage range does the UT12B detect?

The detection range is 90 VAC to 1000 VAC. It does not detect DC voltage.

How do I turn the UT12B on and off?

Press the power button once to turn it on (beep and LED flash twice). To turn off, press and hold the power button for two seconds until a long beep sounds. It also auto-powers off after about 3 minutes of inactivity.

Can I mute the beeper?

Yes. After turning on, press the power button once to toggle to silent mode (beeper off, LED only). Press again to return to beeper mode. Muting helps save battery.

What do the beeps and LED flashes mean?

When detecting voltage, a beep and LED flash indicate AC voltage present. On startup, two beeps/flashes mean normal operation. Auto power-off is signaled by two beeps then one long beep.

How do I replace the batteries?

Disconnect from any circuit. Remove the back housing by pulling it off (use thumb on probe cap). Replace with 2 x 1.5V AAA batteries observing polarity. Push the housing back into place.

Is the UT12B safe for high voltage?

Yes, it is rated CAT IV 1000V and double insulated for safety. Always keep fingers behind the probe guard and follow the manual's safety instructions.

What should I do if the UT12B doesn't respond?

Check the batteries: if the LED fails to flash on startup or the beep is weak, voltage may be below 2V. Replace batteries if needed. Also ensure the device is not wet or damaged.

Can I test DC voltage with the UT12B?

No, the UT12B is designed only for AC voltage (90-1000V). It will not respond to DC voltage.

How should I clean and store the UT12B?

Clean the casing with a damp cloth and mild detergent. Do not use abrasives or solvents. Store in a dry place between 10°C and 50°C.

USER MANUAL UT12B Uni-T

Close-up of a hand using a tool to adjust or install electrical components on an electrical panel (no visible text or symbols)

Overview

This Operating Manual covers information on safety and cautions. Read and understand all of the instructions and safety information in this manual before operating or servicing this tool. Failure to understand how to safely operate this tool could result in an accident causing serious injury or death.

UT12B is intended to check for the presence of AC voltage, signaling the user with a beep and a flashing LED.

Safety Information

This unit complies with the standards EN61010-1, UL61010-1 and CASC 22.1 No. 61010-1 safety measurement requirement: in pollution degree 2, overvoltage category (CAT. IV 1000V)

CAT.IV: Primary supply level, overhead lines, cable systems etc. Some examples include cables,

meters, transformers, and other exterior equipment owned by the power utility.

Use the unit only as specified in this operating manual, otherwise the protection provided by the unit may be impaired.

• Do not use the unit if it is wet, damaged or cannot operate correctly.
• Do not apply more than the rated voltage between the probe tip and earth ground.
• When the unit working at voltage over 30V in AC, special care should be taken for there is danger of electric shock.
• Follow the local countries safety requirements and standards.

Warning

● This unit is only designed for the specialist who has certain technical knowledge to use
- This unit is intended to check for the presence of AC voltage, the voltage range is 90\~1000V. Make sure the tested inductor possible voltage range before carrying out checking.
- When you cannot sure the tested inductor voltage range, the unit does not have any response. It does not mean the tested inductor does not have dangerous voltage, do not use any part of the body to touch the tested inductor.
- When carrying out checking, keep your fingers behind the probe tip finger guards.

International Electrical Symbols

Symbols used on the Meter and in this manual are explained below:

	Double Insulated
	Warning. Refer to the Operating Manual
	Danger of electric shock
CE	Conforms to Standards of European Union

Specifications

● Indicators: LED and Beep
● Voltage range: 90VAC \~ 1000VAC
● Measurement Category IV 1000V per IEC61010
- Temperature:
Operating: -10\~50°C
Storage: 10\~50°C
● Humidity: 95%
- Altitude: 2000m

• Pollution Degree 2
  ● Battery: 2 x 1.5V AAA
  1) Turn the unit on by pressing the power button once, the unit beeps and LED flashes two times. When the unit is under standby mode, the LED keeps flashing two times in every 1.5 seconds.
  2) Place the probe tip on or near the circuit or unit to be tested. Beep and flashing LED indicate the presence of voltage (90VAC to 1000VAC).
  3) To turn off the beeper, you could press the power button once after turning on the unit, then you will hear a beep sound indicating the beeper is off. After the beeper is off, only LED will flash during checking. This way could save battery.
  Press power button to toggle between beeper mode and silent mode. Beep two times enters beeper mode, while beep one time enters silent mode.
  4) In order to save battery, the unit will auto power off when it is not used for around 3 minutes.
  The beeper sounds 2 times continuously and then one long beep means the unit is power off.
  5) Press and hold the power button for two seconds to turn the unit off, there will be one second long beep.

Operation

Battery Indication

The LED will not flash when you turn the unit on or during checking if the battery is less than 2V. The beep sounds will still have but may be weaker.

Maintenance

Battery Replacement

1) Disconnect the unit from the circuit.
2) One hand holds the unit. Place another hand's thumb on the probe cap as the figure below

Illustration of a hand holding a pen or tool, with an arrow indicating motion (no text or symbols)

Figure 1

3) Pull back the back housing as the figure below

Illustration of two hands holding a tool with an arrow indicating direction (no text or symbols)

Figure 2

4) Replace the batteries (observe polarity). 2 x1.5V AAA

5) Push back the back housing.

Cleaning

Periodically wipe the case with a damp cloth and mild detergent; do not use abrasives or solvents.

\*END\*

This operating manual is subject to change without notice.

UNI-T®

UNI-TREND TECHNOLOGY (CHINA) CO., LTD.
No6, Gong Ye Bei 1st Road,
Songshan Lake National High-Tech Industrial
Development Zone, Dongguan City, Guangdong Province, China
Guangdong Province, Ch Tel: [phone]
http://www.uni-trend.com