UT139S True RMS Digit Multimeter AC DC Voltage

The UNI-T UT139S is a professional-grade true RMS digital multimeter designed for electricians, electrical maintenance personnel, and industrial field testing. It is the high-end model in the UT139 series. The product integrates accurate measurement, safety protection, and user-friendly design.

It features a black EBTN high-definition display, suitable for operation in low-light environments. Integrating core functions such as low-pass filtering (LPF) and low-impedance input (LoZ), it can handle measurement challenges such as nonlinear loads and harmonic interference in complex electrical environments. It meets CAT III 600V safety standards and is certified by cETLus and CE, balancing professionalism and durability.

Product Description from the Supplier

Xi'an Mingxi Taida Information Technology Co., Ltd. brings over 12 years of industry expertise to deliver cutting-edge measurement and control solutions.With progressed computerization forms and strict quality control, we guarantee each item meets the most noteworthy guidelines for proficient applications.

Description

With the widespread adoption of industrial automation and the extensive use of frequency converters, new energy electrical equipment, and precision control circuits, traditional multimeters struggle to address measurement challenges such as harmonic interference, false voltage, and distorted waveforms. Leveraging over 20 years of experience in testing and measurement technology, UNI-T has developed the Model UT139S True RMS Digit Multimeter AC DC Voltage to address these practical difficulties in electrical work. This model integrates core technologies such as true RMS, LPF, and LoZ, while optimizing display and safety design. Balancing accuracy, stability, and ease of use, it has become a core tool for industrial electrical testing.

The UT139S, as the series flagship model, focuses on high-end needs in industrial environments, electrical maintenance, and precision repair, filling the gap in ordinary multimeters for complex interference environments and high-precision measurement environments.

Features of the UT139S True RMS Digit Multimeter AC DC Voltage

• Accurately measures nonlinear loads and distorted waveform signals, avoiding errors caused by the average response of ordinary multimeters. Suitable for frequency converters, motor control, and other scenarios
• Built-in low-pass filter (LPF) filters carrier frequency and harmonic interference; equipped with LoZ low-impedance input, accurately identifies power frequency spurious voltages, eliminating false judgments
• Black EBTN screen with 6000 large digital display and backlighting for low-light environments; paired with a 31-segment analog bar to track numerical trends in real time and quickly capture dynamic signals.
• CAT III 600V safety rating, withstands 6kV pulse voltage, lightning strike and surge protection, full-range protection to prevent overload damage.
• Supports MAX/MIN extreme value recording, REL relative measurement, data hold, and automatic/manual range switching, adaptable to complex working conditions for efficient detection.
• Ergonomic non-slip shell, integrated stand design, easy to hold and place on a table; lightweight design, suitable for outdoor and confined space operation.

Functions

• AC/DC Voltage (ACV/DCV): 600V range, suitable for mains power and industrial control circuit measurement.

• AC/DC Current (ACA/DCA): 10A range, covering conventional circuits and load current detection. Resistance (Ω): 60MΩ range, supports circuit continuity and component resistance measurement.

•Capacitance (C): 100000μF range, suitable for filter capacitors and energy storage component detection.

•Frequency (Hz): 10MHz range, measures signal frequency and motor speed signals.

•Temperature (°C): Contact temperature measurement, suitable for equipment surface and ambient temperature detection.

•Diode Test: Detects diode forward conduction characteristics and circuit polarity.

•Continuity/Open Circuit Buzzer: Quickly troubleshoots short circuits and open circuits; buzzer alerts eliminate the need to constantly monitor the screen.

​​​​​​​

• NCV Non-Contact Voltage Detection: Induces electric field strength for non-contact detection of charged bodies, improving work safety.

• MAX/MIN Extreme Value Recording: Automatically captures the maximum/minimum values during measurement and records signal fluctuations.

• REL Relative Measurement: Subtracts test lead resistance and initial values to accurately measure minute differences.

• Data Hold: Locks measured values for easy recording and reading.

•Automatic/Manual Range: Automatically adapts the range for improved efficiency; manual range locks in accuracy.

•Automatic Power Off: Automatically shuts off power after 15 minutes of inactivity to extend battery life.

Sepecifications

Technical Specifications-UT139S True RMS Digit Multimeter AC DC Voltage

DCV

• Measurement range: 600V

•Accuracy: ±(0.5%+3 digits)

•Input impedance: 10MΩ

ACV ( True RMS )

•Measurement range:600V

•Accuracy:±(0.8%+5 digits)

•Frequency range: 45Hz-400Hz

DCA

•Measurement range:10A

•Accuracy:：±(1.2%+5 digits)

ACA ( True RMS )

•Measurement range:10A

•Accuracy:±(1.5%+5 digits)

•Frequency range:45Hz-400Hz

Resistance

•Measurement range:60MΩ

•Accuracy:±(0.8%+3 digits)

•On/off beep: ≤50Ω beep notification

Capacitance

•Measurement range:100000μF

•Accuracy:±(2.5%+5 digits)

Frequency

•Measurement range:10MHz

•Accuracy:±(0.1%+3 digits)

Software User Manual

The UT139S True RMS Digit Multimeter AC DC Voltage is an offline measurement tool that requires no additional host computer software. It can operate independently upon power-on, simplifying the usage process and making it suitable for rapid on-site testing environments.

Advanced Function Operation

• MAX/MIN: Press once to start recording extreme values, press again to switch between displaying maximum/minimum values, long press to exit.

• REL: Press once to enable relative measurement, subtracting the current initial value, press again to exit.

• HOLD: Press once to lock the current reading, press again to unlock.

• NCV Voltage Testing: Turn the knob to the NCV position, bring it close to a charged object, the analog bar on the screen and the buzzer will simultaneously indicate the electric field strength.

Custom Design

We get it that standard arrangements do not continuously meet one of a kind prerequisites. Our experienced building group gives comprehensive OEM/ODM customization administrations. Whether you require adjusted recurrence ranges, specialized activating alternatives, or custom frame components, we work closely with you to create the idealize arrangement. Our adaptable plan approach guarantees your particular application needs are completely tended to whereas keeping up our quality standards.

Why Select MXTD

Proven Encounter: Over 12 a long time of specialized skill in estimation and control frameworks development.

Expert Designing: Our gifted R&D group ceaselessly innovates to convey cutting-edge arrangements that keep you ahead of industry demands.

Quality Confirmation: Strict fabricating forms and comprehensive testing conventions guarantee dependable, steady performance.

Comprehensive Back: From starting meeting through progressing support, our committed group gives responsive specialized assistance.

Secure Conveyance: Collaborating with trusted coordinations suppliers guarantees secure, followed, and safety net provider shipment of your equipment.

Customer Center: We prioritize your victory with standard follow-ups, fast issue determination, and personalized benefit approaches.

Warning

! Before opening the rear cover,switch of the powersupply (remove test leads from the input terminal and the circuit)

! Clean the case with a damp cloth and detergent.Do not use abradants or solvents

! If there is any malfunction,stop using the deviceand send it to maintenance

! The maintenance and service must be implementedby qualified professionals or designated departments

! Do not input voltage over 600Vrms,or it may pose shock hazard.Be cautious when measuring high voltage

! Switch off the power supplyto the circuit,and fully discharge all capacitors. Do not input over 60V DC or 30VAC or it willpose shock hazard

Contact Us

If you are looking for an affordable excellent choice. As the UT139S True RMS Digit Multimeter product line, the UT139S True RMS Digit Multimeter AC DC Voltage is highly competitive in the mid-range Digit Multimeter market.It doesn't make you pay for features you don't need, yet it fully meets your requirements in terms of key measurement capabilities.

Email: manager03@mxtdinfo.com /  manager02@mxtdinfo.com