The UNI-T UT572 is a professional-grade earth resistance tester designed for precise ground system evaluation and soil resistivity analysis. Engineered for electrical contractors, power system technicians, and facility maintenance professionals, this advanced instrument delivers reliable measurements for power equipment wiring, lightning protection systems, and telecommunications infrastructure. With multi-wire testing capabilities, automated connection verification, and interference detection, the UT572 ensures accurate ground resistance evaluation in diverse field conditions to maintain safety standards and electrical system integrity.
The UNI-T UT572 delivers exceptional measurement precision with dual test frequencies (94Hz and 128Hz), enabling accurate earth resistance readings even in environments with electrical interference. With measurement ranges spanning from 4Ω to 40kΩ and resolution down to 0.01Ω, it provides the detailed data necessary for comprehensive ground system evaluation. The tester automatically detects potentially disruptive interference voltage up to 50V and identifies frequencies between 40Hz-500Hz that could affect measurement integrity.
The specialized soil resistivity function allows precise evaluation of ground conditions for new installations, with adjustable test distances from 1m to 40m, providing critical data for optimal grounding electrode placement. For advanced diagnostics, the UT572 includes dedicated RH and RS testing capabilities to identify individual electrode contributions to overall resistance, along with compensating resistance (RK) evaluation to account for test lead effects in high-precision measurements.
The UT572 combines essential earth resistance measurements with specialized functions to deliver complete grounding system diagnostics:
The complete measurement capabilities make the UT572 suitable for both installation verification and maintenance testing across industrial, commercial, and utility applications, ensuring grounding systems meet safety standards and provide intended protection.
The UNI-T UT572 is engineered for reliable field operation with features designed for practical use in diverse environments:
These durability and convenience features ensure the UT572 performs reliably across various field environments, from urban electrical installations to remote telecommunications sites and utility infrastructure.
Electrical engineers and technicians rely on the UT572's precision and versatility for:
Lightning protection specialists leverage the UT572's specialized features for:
Telecommunications technicians depend on the UT572's precision for:
Facility maintenance professionals utilize the UT572 for:
| Measurement | Range | Accuracy |
|---|---|---|
| Earth Resistance (Re) | 4Ω | ±(3%+15) |
| Earth Resistance (Re) | 40Ω/400Ω/4kΩ/40kΩ | ±(3%+5) |
| Soil Resistivity (ρ) | 4Ω | ±(3%+15) |
| Soil Resistivity (ρ) | 40Ω/400Ω/4kΩ/40kΩ | ±(3%+5) |
| Disturbance Voltage (Ust) | 50V (DC voltage/40Hz~500Hz) | ±(3%+3) |
| Disturbance Frequency (Fst) | 40Hz~500Hz | ±(1%+2) |
| Feature | UNI-T UT572 | UNI-T UT625A | UNI-T UT620T |
|---|---|---|---|
| Primary Function | Earth Resistance & Soil Resistivity | Low Resistance Testing (High Current) | DC Resistance Testing |
| Measurement Method | 2/3/4-wire measurement | 4-wire measurement | 4-wire measurement |
| Measurement Range | 0.01Ω to 40kΩ | 0.1μΩ to 1000mΩ | 100μΩ to 1MΩ |
| Test Current | Test signal current | 5A to 100A DC | 40mA to 10A |
| Display | LCD with backlight | 7-inch color LCD | 7-inch color LCD |
| Data Storage | 20 sets | 200 sets | 9999 sets |
| Power Supply | Battery powered (1.5V x 8) | AC power (198V-242V) | Rechargeable battery or AC power |
| Primary Applications | Grounding systems, Lightning protection | Circuit breakers, High-current connections | Transformers, Motor windings |
| Weight | 1.1kg | 6.4kg | 7.1kg |
| Price Point | Standard | Premium | Premium |
What is the difference between 2-wire, 3-wire, and 4-wire earth resistance testing?
The UNI-T UT572 supports multiple testing methods to accommodate different field requirements. The 2-wire method is quickest for basic testing but may include lead resistance in measurements - useful for simple verification. The 3-wire method (most common) uses a third probe to eliminate test lead resistance from the measurement, providing more accurate readings in most applications. The 4-wire method adds a fourth connection to completely eliminate the effects of both lead and contact resistance, providing the highest precision for critical installations. This versatility allows technicians to select the appropriate testing protocol based on the application's requirements and accuracy needs.
How does soil resistivity testing benefit new electrical installations?
The UT572's soil resistivity testing function provides critical data for optimizing new grounding system installations. By measuring the specific resistivity of soil (in ohm-meters) at various depths and locations, engineers can identify the optimal placement and design for grounding electrodes. This function uses the Wenner four-pin method with adjustable spacing from 1 to 40 meters to create a soil resistivity profile. Proper soil resistivity analysis can reduce installation costs by determining the most efficient ground electrode configuration, minimize the number of ground rods required, and ensure the system meets resistance requirements for electrical safety codes and lightning protection standards.
Why is the ability to detect interference voltage and frequency important?
The UT572's ability to automatically detect interference voltage up to 50V and measure frequencies between 40Hz-500Hz is crucial for ensuring measurement accuracy. In industrial and urban environments, stray voltages and electromagnetic fields from nearby power lines, equipment, or ground currents can significantly skew earth resistance readings, potentially hiding dangerous conditions. By identifying and measuring this interference before testing, the UT572 helps technicians determine if conditions are suitable for accurate measurements or if alternative testing methods are needed. This capability is especially valuable when working near operational electrical equipment, substations, or in locations with multiple grounding systems that may introduce ground loops and stray currents.
What advantages does the RH and RS test capability provide?
The UT572's RH and RS test capability allows technicians to measure individual earth electrode resistance components separately, providing detailed diagnostic information not available with basic testers. This function helps identify which specific components in a grounding system are contributing to high resistance readings, allowing targeted improvements rather than complete system replacement. For example, by separately measuring the resistance of auxiliary test electrodes (RH) and the actual ground electrode under test (RS), technicians can isolate issues to specific connection points, soil conditions, or electrode corrosion. This specialized diagnostic capability significantly improves troubleshooting efficiency and reduces maintenance costs by pinpointing exactly where improvements are needed in complex grounding systems.
UNI-T stands behind the UT572 with comprehensive technical support and a 1-year warranty. Our dedicated support team is available to assist with application questions, measurement techniques, and warranty service.
The UNI-T UT572 Advanced Earth Resistance Tester delivers exceptional accuracy, versatility, and reliability for professionals responsible for electrical safety and lightning protection systems. With its multi-wire measurement capabilities, interference detection, and comprehensive accessory kit, it provides the detailed grounding system data needed to ensure regulatory compliance and protect equipment and personnel from electrical hazards and lightning damage.
Order Your UNI-T UT572 Today and Experience Professional-Grade Earth Resistance Measurement Capabilities
