1. Įvadas
The UNI-T UT271 Series Clamp-on Ground Resistance Tester is a professional instrument designed for measuring ground resistance, AC current, and AC leakage current. This series includes models UT271A, UT271B, and UT271C, each offering specific capabilities as detailed in the specifications. This manual provides essential information for the safe and effective operation, setup, maintenance, and troubleshooting of your device.
2. Saugos informacija
Please read and understand all safety warnings and operating instructions before using this instrument. Failure to follow these instructions may result in electric shock, fire, or serious injury. Keep this manual for future reference.
- Visada laikykitės vietinių ir nacionalinių saugos taisyklių.
- Nenaudokite matuoklio, jei jis atrodo pažeistas arba veikia neįprastai.
- Ensure the measurement circuit is de-energized before connecting or disconnecting the clamp, jei taikoma.
- Do not operate the meter in explosive atmospheres or in the presence of flammable gases or dust.
- The device complies with safety standards: IEC61010-1 (CATII 300V, CATIV 150V, pollution level 2); IEC61010-031; IEC61557-1 (Grounding Resistance); JJG 1054-2009 Verification Regulations for Clamp ant įžeminimo varžos matuoklio.
3. Produktas baigtasview ir Savybės
The UT271 series features a robust design for reliable performance in various industrial and electrical testing environments. Its clamp-on design allows for non-contact measurement of ground resistance and current.

3.1 paveikslas: Priekyje view of the UNI-T UT271C Clamp-on Ground Resistance Tester, showing the clamp jaw, display, and control buttons.

3.2 paveikslas: Atgal view of the UNI-T UT271 Clamp-on Ground Resistance Tester, showing the battery compartment and warning labels.
Pagrindinės funkcijos:
- Atsparumo diapazonas: 0.010 – 300 Ω (specific ranges vary by model, refer to specifications).
- Žandikaulio atidarymas: Φ32mm, suitable for measuring most grounding busbars.
- Duomenų saugykla: Up to 500 sets of data (UT271B, UT271C models).
- Ekranas: 4-digit LCD display, capable of simultaneous display of Ω and A on the same screen (UT271B, UT271C).
- Quick Self-Check: Performs a self-check on startup.
- Full Automatic Gear Shifting: Simplifies operation.
- Greitas matavimas: Approximately 1 measurement per second.
- CE sertifikatas: Conforms to European safety standards.

3.3 paveikslas: Baigėsiview of key features for the UNI-T UT271A model, highlighting its measurement capabilities and display characteristics.

3.4 paveikslas: The 32mm circular jaw of the UT271C clamp meter, demonstrating its suitability for measuring various grounding busbars in practical applications.
4. Sąranka
4.1 Unpacking and Checking Accessories
Upon receiving your UNI-T UT271 Series tester, carefully unpack all components and verify that the following items are included:
- UNI-T UT271 Series Instrument: 1 unit
- Test loop: 1 Ω, 10 Ω (Standard test rings)
- Cloth bag: 1 PCS
- Instruction manual: 1 PCS (This document)
- Warranty card/certificate of conformity: 1 PCS

4.1 paveikslas: All standard accessories included with the UNI-T UT271 series clamp meter, ensuring you have everything needed for operation.
4.2 Akumuliatoriaus įdėjimas
The UT271 series operates on DC 6V, requiring four No.5 alkaline dry batteries (LR6 1.5V X 4). To install or replace batteries:
- Įsitikinkite, kad prietaisas yra išjungtas.
- Įrenginio gale suraskite baterijų skyrių (žr. 3.2 pav.).
- Atidarykite akumuliatoriaus skyriaus dangtelį.
- Insert four LR6 1.5V alkaline batteries, observing the correct polarity (+/-) as indicated inside the compartment.
- Saugiai uždarykite akumuliatoriaus skyriaus dangtelį.
5. Naudojimo instrukcijos
5.1 Įjungimas / išjungimas ir pagrindinės funkcijos
- Maitinimas: Paspauskite maitinimo mygtuką (ⓒ) to turn on the device. It will perform a quick self-check.
- Išjungti: Paspauskite ir palaikykite maitinimo mygtuką (ⓒ) to turn off the device. The device may also have an auto-power-off feature to conserve battery.
- Duomenų sulaikymas: Paspauskite LAIKYTI mygtuką, kad sustabdytumėte dabartinį rodmenį ekrane. Paspauskite dar kartą, kad atleistumėte.
- Memory (MEM): For models UT271B and UT271C, press the MEM button to save the current measurement. Refer to the device's on-screen prompts for navigating saved data.
5.2 Measuring Ground Resistance
The UT271 series uses a clamp-on method for ground resistance measurement, eliminating the need for auxiliary electrodes and disconnecting the ground system.
- Ensure the circuit to be measured is safe to access.
- Atidarykite klamp žandikaulį paspausdami gaiduką.
- Padėkite klamp around the grounding conductor or busbar. Ensure the jaw is fully closed and there are no gaps.
- The device will automatically select the appropriate range and display the ground resistance value in Ohms (Ω).
- For accurate measurements, ensure the contact surfaces are clean.
5.3 Measuring AC Current and Leakage Current
The UT271 series can also measure AC current and leakage current through the same clamp mechanizmas.
- Atidarykite klamp žandikaulis.
- Padėkite klamp around the conductor carrying the AC current or the conductor where leakage current is to be measured.
- Ensure the jaw is fully closed.
- The device will display the AC current in Amperes (A). For leakage current, ensure only the specific conductor or group of conductors relevant to the leakage path is clampred.
5.4 Taikymo scenarijai
The UT271 series is suitable for various applications:
- Power Engineering: Checking the resistance value of the grounding grid during substation construction or renovation to meet safety standards.
- Transmission Tower: Evaluating the effectiveness of grounding systems for transmission towers to protect equipment from electrical faults like lightning strikes and overvoltages.
- High-rise Buildings: Installing lightning protection systems requires accurate grounding resistance measurement to ensure effectiveness.
- Subway Construction Projects: Grounding resistance testing is essential for the electrical facilities of underground railway projects to ensure operational safety.

5.1 paveikslas: Examples of the UNI-T UT271 series in use for different applications, including power engineering, transmission tower grounding, AC current measurement, and leakage current measurement.
6. Priežiūra
6.1 Valymas
To maintain the accuracy and longevity of your instrument:
- Nuvalykite casing su reklamaamp audiniu ir švelniu plovikliu. Nenaudokite abrazyvinių ar tirpiklių.
- Laikykite klamp jaw clean and free of dust or debris to ensure proper closure and accurate readings.
6.2 Saugykla
When not in use, store the instrument in its cloth bag in a dry, cool place, away from direct sunlight and extreme temperatures. The recommended storage temperature is -20°C to 60°C (-4°F to 140°F) with relative humidity below 80% RH.
6.3 Akumuliatoriaus keitimas
Replace batteries promptly when the low battery indicator appears on the display to ensure continuous accurate operation. Refer to Section 4.2 for battery installation instructions.
7. Problemų sprendimas
If you encounter issues with your UT271 series tester, consider the following common problems and solutions:
- Nėra ekrano / įjungtas maitinimas: Patikrinkite, ar baterijos tinkamai įdėtos ir ar jos pakankamai įkrautos. Jei reikia, pakeiskite baterijas.
- Netikslūs rodmenys: Įsitikinkite, kad klamp jaw is fully closed and clean. Verify the measurement setup. Check for external interference signals; the device automatically identifies and indicates "Noise" when interference is high.
- "Low Battery" Prompt: Replace all four LR6 1.5V alkaline batteries.
- Rodymo klaida: Power off the device, wait a few seconds, and power it back on. If the error persists, contact customer support.
8. Specifikacijos
The following table details the technical specifications for the UNI-T UT271 series. Note that some features and ranges may vary between models (UT271A, UT271B, UT271C).
| Funkcija | Diapazonas | Rezoliucija | Tikslumas | UT271A | UT271B | UT271C |
|---|---|---|---|---|---|---|
| Atsparumas | 0.010-0.099Ω | 0.001Ω | ± (1 % rodmens + 0.01 Ω) | √ | √ | √ |
| 0.100-0.990Ω | 0.01Ω | ± (1 % rodmens + 0.01 Ω) | √ | √ | √ | |
| 1.00-49.9Ω | 0.1Ω | ± (1 % rodmens + 0.1 Ω) | √ | √ | √ | |
| 50.0-99.5Ω | 0.5Ω | ± (1.5 % rodmens + 0.5 Ω) | √ | √ | √ | |
| 100Ω-199Ω | 1Ω | ± (2 % rodmens + 1 Ω) | √ | √ | √ | |
| 200Ω-395Ω | 5Ω | ± (5 % rodmens + 5 Ω) | - | √ | √ | |
| 400Ω-590Ω | 10Ω | ± (10 % rodmens + 10 Ω) | - | √ | √ | |
| 600Ω-1000Ω | 20Ω | ± (20 % rodmens + 20 Ω) | - | √ | √ | |
| Dabartinė | 0.00mA-9.99mA | 0.01 mA | ± (2.5 % rodmens + 1 mA) | √ | √ | √ |
| 10.0mA-99.9mA | 0.1 mA | ± (2.5 % rodmens + 5 mA) | √ | √ | √ | |
| 100mA-299mA | 1 mA | ± (2.5 % rodmens + 10 mA) | √ | √ | √ | |
| 0.30A-2.99A | 0.01A | ± (2.5 % rodmens + 0.1 A) | √ | √ | √ | |
| 3.0A-9.9A | 0.1A | ± (2.5 % rodmens + 0.3 A) | - | √ | √ | |
| 10.0A-20.0A | 0.1A | ± (2.5 % rodmens + 0.5 A) | - | √ | √ | |
| Maitinimas | DC 6V, No.5 alkaline dry battery (LR6 1.5V X 4) | |||||
| Žandikaulio dydis | Φ32 mm | |||||
| Ω + A Display | Palaikymas (tik UT271B, UT271C) | |||||
| Duomenų saugykla | 500 komplektai | |||||
| Trikdžių testas | Automatiškai identifikuoja trukdžių signalus, kuriuos rodo „Triukšmo“ simbolis, kai trukdžių srovė yra didelė | |||||
| Baterijos tūristage | Žemas akumuliatoriaus tūristage raginimas | |||||
| Elektros energijos švaistymas | Maksimali srovė yra apie 60 mA | |||||
| Išmatuokite laiką | Kartą per sekundę | |||||
| LCD dydis | 46 mm × 36 mm | |||||
| Šeimininko dydis | 260 mm × 105 mm × 60 mm | |||||
| Izoliacija | 20MΩ | |||||
| Atsparumas slėgiui | 3700 V kintamoji srovė / rms | |||||
| Svoris | 818g | |||||
| Operacija | -10°C~40°C; 70% santykinė oro drėgmė | |||||
| Sandėliavimas | -20°C~60°C; 80% santykinė oro drėgmė | |||||
| Magnetinis laukas | <40A/m; <1V/m | |||||
| Saugos taisyklės | IEC61010-1 (CATII 300V, CATIV150V, pollution level 2); IEC61010-031; IEC61557-1 (Grounding Resistance); JJG 1054-2009 Verification Regulations for Clamp Įžeminimo varžos matuoklis | |||||

8.1 paveikslas: Comprehensive technical specifications for the UT271 series, outlining performance parameters and compliance standards.
Bendra informacija apie gaminį:
- Gamintojas: UNI-TREND TECHNOLOGY (CHINA) CO., LTD.
- Modelio numeris: YQ-UT271A (Specific model for this product listing)
- Kilmės šalis: Kinija
9. Garantija ir palaikymas
UNI-T products are designed for reliability and performance. This instrument comes with a standard warranty against defects in materials and workmanship. Please refer to the warranty card included with your product for specific terms and conditions.
For technical support, service, or warranty claims, please contact your local UNI-T distributor or the point of purchase. Ensure you have your product model number (UT271A, UT271B, or UT271C) and serial number available when seeking assistance.