UT139S True RMS Digital Multimeter

The UT139S True RMS Digital Multimeter is a high-performance measuring instrument designed for professional technicians, engineers, and advanced electronics users who require exceptional precision, reliability, and stability in their diagnostic workflows. With True RMS capability, the UT139S delivers accurate readings even in non-linear or distorted electrical signals, making it an ideal tool for modern power electronics, industrial systems, and sensitive electronic circuits.

Engineered with advanced safety features and intelligent measurement functions, the UT139S is suitable for workshops, industrial maintenance, electrical installations, HVAC troubleshooting, and engineering labs. Its rugged construction, ergonomic design, and large backlit display make it a comfortable and dependable partner for both indoor and field operations.

Key Features

• True RMS technology for accurate measurements on complex or non-sinusoidal waveforms.

• AC/DC Voltage measurement ideal for household circuits, industrial machinery, and power supplies.

• AC/DC Current testing suitable for electrical panels, motors, and control systems.

• Resistance, continuity, and diode testing for diagnosing PCB faults and wiring issues.

• Capacitance measurement ideal for LED drivers, inverter circuits, power supply repair, and electronics troubleshooting.

• Frequency testing supports modern switching power supplies and signal analysis.

• NCV (Non-Contact Voltage Detection) for fast and safe electrical presence checking.

• Live Wire detection enhances safety during installation and repair tasks.

• Built-in flashlight for working in dark or confined environments.

• Large backlit LCD display for easy visibility in all lighting conditions.

• Overload protection across all ranges for safe and durable operation.

• Ergonomic rubber housing for enhanced grip and impact protection.

• Auto range function for fast, intuitive measurement without manual adjustments.

Technical Specifications (Data Sheet Highlights)

• DC Voltage: 60mV – 600V

• AC Voltage: 60mV – 600V (True RMS)

• DC Current: 600µA – 10A

• AC Current: 600µA – 10A (True RMS)

• Resistance: 600Ω – 60MΩ

• Capacitance: 9.999nF – 99.99mF

• Frequency: Up to 10MHz

• Temperature Measurement: -40°C to 1000°C (with K-type probe)

• Safety Rating: CAT III 600V / CAT II 1000V

• Display: Large backlit LCD

• Power: 2×AA batteries

• Protection: Full-range overload protection and robust internal circuitry

• Additional Functions: NCV detection, live wire test, flashlight, auto power-off

Why Professionals Prefer the UT139S

The UT139S True RMS Digital Multimeter stands out because of its powerful measurement capabilities, superior safety design, and versatile performance across industrial, electrical, and electronic applications. Whether you are analyzing distorted waveforms, troubleshooting control panels, repairing power electronics, or conducting laboratory experiments, the UT139S ensures precise and dependable results that meet modern engineering standards.