UT273 Clamp Earth Ground Tester (Discontinued)

The UT273 Clamp Earth Ground Tester (Discontinued) is a professional clamp-on measuring instrument designed for accurate and efficient earth ground resistance testing without the need for auxiliary test rods. Although this model is now discontinued, it remains widely recognized for its reliability, ease of use, and exceptional measurement stability in industrial and commercial grounding applications.

Engineered for electrical engineers, facility technicians, industrial safety inspectors, and utility maintenance teams, the UT273 Clamp Earth Ground Tester (Discontinued) allows ground resistance and leakage current measurements to be carried out safely on active grounding circuits. This clamp-on method eliminates the need to disconnect grounding conductors, providing a faster, safer, and more convenient alternative to traditional fall-of-potential testing—especially in multi-grounded systems.

Equipped with a precision current transformer and a fast-response microprocessor, the UT273 delivers stable readings even in environments with electrical noise. Its large backlit LCD screen ensures excellent visibility in outdoor, low-light, or field conditions. The instrument also supports essential functions including auto-ranging, MAX/MIN capture, data hold, and automatic power-off, helping technicians work more efficiently during extended testing sessions.

Compact, rugged, and designed for durability, the UT273 features a strong clamp mechanism that fits grounding electrodes, busbars, bonding conductors, and various grounding rods. Its industrial-grade housing ensures long-term performance even in harsh or demanding electrical environments such as substations, power distribution networks, lightning protection systems, telecommunications towers, and industrial installations.

Despite being discontinued, the UT273 remains a trusted tool among professionals due to its robust build quality and dependable measurement accuracy.

Key Features

• High-accuracy clamp-on earth ground resistance tester

• Measures ground resistance without disconnecting cables

• Leakage current measurement capability

• Auto-ranging & fast digital sampling

• MAX/MIN measurement capture

• Large backlit LCD for outdoor and dim environments

• Rugged, ergonomic clamp structure

• Ideal for substations, telecom grounding, industrial plants & electrical safety inspections

• Perfect for preventive maintenance and troubleshooting

Technical Datasheet

Ground Resistance Measurement

• Range: 0.010Ω to 1200Ω

• Accuracy: ±(1% + 0.02Ω) depending on range

• High-stability current transformer

Leakage Current Measurement

• Range: 0.00mA to 30A AC

• Accuracy: ±(2% + 5 digits)

Jaw Opening

• 28mm clamp size

• Suitable for grounding rods, busbars & bonding conductors

Display

• Large backlit LCD

• Displays resistance, current, MAX/MIN

• Low-battery indicator

Functions

• Auto-range

• Auto power-off

• Data hold

• Self-calibration

Power

• 4 × AA batteries

• Long operating lifetime

Environmental Conditions

• Operating temperature: 0°C – 40°C

• Humidity: < 80% RH

Design & Build

• Industrial ABS housing

• Shock-resistant clamp mechanism

• Durable ergonomic design for field use