Digital Multimeter, True RMS, 600 V, NCV/LIVE, UT123D UNI-T

UNI-T UT123D Digital Multimeter, True RMS, 600 V, NCV/LIVE

The UNI-T UT123D is a compact digital multimeter designed for household electrical work, DIY projects and basic electrical/electronic troubleshooting. It can automatically identify commonly used measurement functions and select the appropriate range, reducing the need for manual range selection. The UT123D measures AC/DC voltage and current, resistance and capacitance, performs diode and continuity tests, and provides True RMS, NCV and LIVE functions.

Key parameters: True RMS • up to 600 V AC/DC • up to 9.999 A AC/DC • 40 MΩ • 4000 µF • 4099 counts • NCV/LIVE • CAT III 600 V

Key advantages

• Automatic function and range recognition – the meter can recognize the input signal and select an appropriate measurement mode, simplifying everyday operation.
• True RMS measurement – provides more representative AC voltage and current readings when the waveform is not a perfect sine wave.
• AC/DC voltage measurement up to 600 V – suitable for a wide range of household electrical and low-voltage electronic checks within the CAT III 600 V rating.
• AC/DC current measurement up to the 9.999 A range – the current input is fused, and inserting the test lead into the current input automatically switches the meter to current measurement.
• Capacitance measurement up to 4000 µF – useful for checking capacitors and basic electronic troubleshooting.
• NCV non-contact voltage detection – provides an indication of an AC electric field without making direct electrical contact with the conductor.
• LIVE function – single-probe detection assists in distinguishing live and neutral conductors, with audible and visual indication.
• EBTN display with up to 4099 counts – provides clearly readable measurements in a compact instrument.
• Data Hold, Auto Power Off and low-battery indication – useful functions for routine work and reduced battery consumption.
• CAT III 600 V rating and 1 m drop resistance – designed for household electrical measurements within the manufacturer's specified safety limits.

Applications

UNI-T positions the UT123D as a residential and entry-level multimeter. It is suitable for basic testing and troubleshooting of electrical wiring, outlets, power supplies, batteries, household appliances and electronic circuits.

Automatic mode recognition is particularly useful for quick everyday measurements, while individual measurement functions can also be selected manually when required.

Compatibility and limitations

The UT123D is a standalone measuring instrument and does not require a computer or mobile application. UNI-T does not specify Bluetooth, USB data communication or data-logging connectivity for this model.

The current UT123D specification also does not list temperature measurement or a dedicated frequency measurement function. The specified AC frequency response relates to AC voltage/current measurement performance and should not be interpreted as a frequency measurement range.

NCV and LIVE are detection/identification aids rather than substitutes for an accurate contact voltage measurement. NCV sensitivity can be affected by cable insulation thickness, socket construction and the distance from the conductor.

Technical specifications

Parameter	Value
Display	EBTN
Maximum display	4099 counts
Sampling rate	Approx. 3 measurements/s
True RMS	Yes
Auto range	Yes
DC voltage	4.000 V / 40.00 V / 400.0 V / 600 V
DC voltage resolution	0.001 V / 0.01 V / 0.1 V / 1 V
DC voltage accuracy	±(0.5% + 3 digits)
AC voltage	4.000 V / 40.00 V / 400.0 V / 600 V
AC voltage resolution	0.001 V / 0.01 V / 0.1 V / 1 V
AC voltage accuracy, 4.000 V	±(1.0% + 5 digits)
AC voltage accuracy, 40.00–600 V	±(0.8% + 3 digits)
AC voltage frequency response	40–400 Hz
DC current	999.9 mA / 9.999 A
DC current resolution	0.1 mA / 0.001 A
DC current accuracy	±(1.0% + 3 digits)
AC current	999.9 mA / 9.999 A
AC current resolution	0.1 mA / 0.001 A
AC current accuracy	±(1.2% + 3 digits)
Resistance, 400.0 Ω	0.1 Ω; ±(1.0% + 2 digits)
Resistance, 4.000 kΩ	0.001 kΩ; ±(0.8% + 2 digits)
Resistance, 40.00 kΩ	0.01 kΩ; ±(0.8% + 2 digits)
Resistance, 400.0 kΩ	0.1 kΩ; ±(0.8% + 2 digits)
Resistance, 4.000 MΩ	0.001 MΩ; ±(1.5% + 3 digits)
Resistance, 40.00 MΩ	0.01 MΩ; ±(2.0% + 5 digits)
Capacitance, 40.00 nF	0.01 nF; ±(4% + 10 digits)
Capacitance, 400.0 nF–400.0 µF	Resolution 0.1 nF–0.1 µF; ±(4% + 5 digits)
Capacitance, 4000 µF	1 µF; ±10%
Diode test	Yes
Continuity test	Yes, audible indication
Continuity buzzer threshold	≤30 Ω – buzzer; ≥50 Ω – no buzzer
NCV	Yes, non-contact AC voltage detection with audible/visual indication
LIVE	Yes, single-probe live/neutral conductor identification
LIVE trigger voltage	≥70 V AC, 50/60 Hz
Data Hold	Yes
Auto Power Off	Yes
Low-battery indication	Yes
Operating temperature	0–40 °C
Reference conditions for stated accuracy	18–28 °C, relative humidity ≤75%
Drop resistance	1 m
Safety category	CAT III 600 V
Standards	IEC 61010-2010, IEC 61326:2012
Certifications listed on UNI-T global product page	CE, UKCA
Power supply	2 × 1.5 V AAA (R03)
Display dimensions	44 × 26 mm
Product dimensions	130 × 65 × 28 mm
Net weight	130 g

Accuracy is stated in the manufacturer's format: ±(% of reading + number of least-significant digits).

Construction and controls

The UT123D features a compact 130 × 65 × 28 mm body and a 44 × 26 mm EBTN display. Common measurement modes can be identified automatically, while other functions can be selected using the control buttons.

Separate COM and current/measurement inputs are provided. When the test lead is inserted into the current input, the meter can automatically enter current measurement mode. Audible and visual indications are used for NCV, LIVE, continuity and battery-status functions.

Important operating and safety notes

• Do not exceed the CAT III 600 V safety category or the manufacturer's specified input limits.
• Exercise increased caution when working above 60 V DC or 30 V RMS AC due to the risk of electric shock.
• Disconnect power and discharge capacitors before resistance, capacitance, diode or continuity measurements.
• Current must be measured with the meter connected in series with the circuit; never connect the current input directly across a voltage source.
• According to the manufacturer's instructions, for currents above 5 A each measurement should last less than 10 seconds, with an interval of more than 5 minutes between such measurements.
• NCV and LIVE are indicative detection functions. For safety-critical verification, confirm the electrical state using an appropriate contact measurement method.

Package contents

• UNI-T UT123D digital multimeter
• 1 pair of test leads