1. Introduction
The UNI-T UT220 series digital clamp meters are advanced instruments designed for precise and reliable electrical measurements. This series includes models UT220, UT221, and UT222, each offering robust performance and safety features for professionals. They are capable of measuring AC and DC currents up to 2000A (2500A for UT222), along with voltage, resistance, frequency, and capacitance, depending on the model.
All models feature full-scale overload protection circuits, ensuring durability and user safety. The large LCD display provides clear and accurate measurement data, making these meters an essential tool for various electrical applications.
2. Product Components and Overview
Familiarize yourself with the main parts of your UNI-T Digital Clamp Meter:
- Pliers: The sensing device that measures AC and DC currents by clamping around a conductor.
- Pliers Turn the Handle: Used to open and close the pliers jaw.
- Function Button: For selecting specific measurement modes or features.
- LCD Display Window: Large screen for displaying measurement data, function symbols, and other information.
- Function Range Selection Dial/Power Switch: Rotary switch to turn the device ON/OFF and select the desired measurement function and range.
- Measurement Input: Ports for connecting test leads for voltage, resistance, frequency, and capacitance measurements.
3. Setup and Initial Use
3.1. Battery Installation
- Ensure the device is turned OFF.
- Locate the battery compartment on the back of the meter.
- Open the battery compartment cover.
- Insert a new 9V (6F22) battery, observing the correct polarity.
- Close the battery compartment cover securely.
Note: Due to logistics reasons, batteries are not included with the product and must be purchased separately.
3.2. Connecting Test Leads (for UT221/UT222)
For measurements requiring test leads (e.g., voltage, resistance, capacitance, frequency, diode, continuity), connect the test leads to the appropriate input jacks:
- Insert the red test lead into the VΩHz+ input jack.
- Insert the black test lead into the COM input jack.
4. Operating Instructions
4.1. Power On/Off
Turn the Function Range Selection Dial to any measurement function to power on the meter. Turn it to the 'OFF' position to power off.
4.2. AC/DC Current Measurement (Clamp Function)
- Turn the Function Range Selection Dial to the 'A~' (AC Current) or 'A=' (DC Current) position.
- Press the pliers turn handle to open the clamp jaw.
- Enclose only one conductor with the clamp jaw. Ensure the jaw is completely closed.
- Read the current value on the LCD display.
Caution: Do not clamp multiple conductors simultaneously for accurate readings. Ensure the circuit is de-energized before clamping if possible, or take appropriate safety precautions.
4.3. Voltage, Resistance, Frequency, Capacitance, Diode, Continuity Measurement (Test Leads)
- Connect the test leads as described in Section 3.2.
- Turn the Function Range Selection Dial to the desired measurement function (e.g., 'V~' for AC Voltage, 'V=' for DC Voltage, 'Ω' for Resistance, 'Hz' for Frequency, 'F' for Capacitance, 'Diode' or 'Continuity' symbol).
- For functions with multiple modes (e.g., AC/DC voltage on the same dial position), use the 'SELECT' button to toggle between modes.
- Apply the test leads to the circuit or component under test.
- Read the measurement value on the LCD display.
4.4. Special Functions
- MAX/MIN: Press the 'MAX/MIN' button to record the maximum or minimum measured value.
- HOLD: Press the 'HOLD' button to freeze the current reading on the display. Press again to release.
- Relative Mode (REL): Available on some models (UT221, UT222). Press 'REL' to set the current reading as a reference, and subsequent measurements will be displayed as a difference from this reference.
- Inrush Current: Available on UT221 and UT222 for measuring the initial surge current when a device is powered on.
- Low Pass Filter (LPF): Available on UT221 and UT222 for filtering out high-frequency noise during AC measurements.
- Data Storage: UT222 model supports storing up to 1000 groups of data. Refer to the specific manual for detailed instructions on data logging.
5. Maintenance
5.1. Cleaning
Wipe the meter's casing with a soft, damp cloth. Do not use abrasive cleaners or solvents. Ensure the meter is completely dry before use.
5.2. Battery Replacement
When the low battery indicator appears on the display, replace the 9V battery as described in Section 3.1. Prompt battery replacement ensures accurate readings and proper device function.
5.3. Storage
When not in use for extended periods, remove the battery to prevent leakage and damage. Store the meter in its carrying case (UT220) or toolbox (UT221/UT222) in a cool, dry place, away from direct sunlight and extreme temperatures.
6. Troubleshooting
If you encounter issues with your clamp meter, consider the following general troubleshooting steps:
- No Display/Faint Display: Check battery installation and replace with a fresh 9V battery if necessary.
- Inaccurate Readings: Ensure test leads are properly connected and not damaged. Verify the correct measurement function and range are selected. For current measurements, ensure only one conductor is clamped.
- No Continuity Beep: Check if the continuity function is selected and test leads are making good contact.
- Overload Indication (OL): The measured value exceeds the selected range. Switch to a higher range or ensure the input is within the meter's capabilities.
For persistent issues, please refer to the detailed user manual provided with your specific model or contact UNI-T customer support.
7. Specifications
The following table outlines the key specifications for the UT220, UT221, and UT222 models:
| Specifications | Range | UT220 | UT221 | UT222 |
|---|---|---|---|---|
| AC Current (A) | 2000A | ±(2.5%+5) | ±(2.5%+5) | |
| 2500A | ±(1.5%+5) | |||
| DC Current (A) | 2000A | ±(2.5%+5) | ||
| 2500A | ±(1.5%+5) | |||
| AC Voltage (V) | 750V | ±(1.2%+5) | ±(1.2%+5) | |
| 1000V | ±(1%+3) | |||
| DC Voltage (V) | 1000V | ±(0.8%+1) | ±(0.8%+1) | ±(0.5%+2) |
| Resistance (Ω) | 20MΩ | ±(1%+2) | ||
| 60MΩ | ±(1%+2) | |||
| 66MΩ | ±(1%+2) | |||
| Capacitance (F) | 60mF | ±(3%+5) | ||
| Frequency (Hz) | 20MHz | ±(0.1%+3) | ||
| 60MHz | ±(0.1%+3) | |||
| Temperature | -40°C~1000°C | ±(1%+10) | ||
| -40°F~1832°F | ±(1%+18) | |||
| Features | ||||
| Display count | 2000 | 6000 | 6000 | |
| Auto range/Diode | √ | √ | √ | |
| Jaw opening | 63mm | 63mm | 63mm | |
| True RMS (AC voltage/AC current) | √ | √ | ||
| Duty cycle | 10%~90% | √ | √ | |
| Continuity buzzer | √ | √ | √ | |
| AC+DC | √ | |||
| Low pass filter | √ | √ | ||
| Inrush current | AC current | √ | √ | |
| Relative mode | √ | √ | ||
| Data hold/MAX | √ | √ | √ | |
| MIN/I-OUT function | √ | √ | ||
| Data storage | 1000 | |||
| Analog bar graph | 66 | 61 | ||
| Full icon display | √ | √ | √ | |
| Low battery indication | √ | √ | √ | |
| Input impedance | ≥10MΩ | √ | √ | √ |
| General Characteristics | ||||
| Power | 9V battery (6F22) (Due to logistics reasons, the shipment does not include batteries) | |||
| Display | 43mm x 30mm | |||
| Product color | Red and grey | |||
| Product net weight | UT220: 389g; UT221/UT222: 726g | |||
| Product size | 298mm x 107mm x 47mm | |||
| Standard accessories | Test leads, output cable (UT221/UT222), thermocouple (UT222) | |||
| Standard individual packing | Gift box, carrying bag (UT220), tool box (UT221/UT222), Manual | |||
Dimensions of UNI-T UT222 Digital Clamp Meter: 298mm length, 100mm width, 48mm depth. The image shows the back, side, and front views with measurements.
8. User Tips
- Always ensure the correct function and range are selected before making any measurement to prevent damage to the meter or the circuit.
- When measuring current with the clamp, isolate the specific wire you want to measure. Clamping multiple wires will result in an inaccurate reading (or zero if currents are balanced).
- For models with True RMS (UT221, UT222), this feature provides more accurate readings for non-sinusoidal AC waveforms, which are common in modern electronics.
- Utilize the 'HOLD' function to capture readings in hard-to-reach or poorly lit areas.
- The leather wristband (included with some models) can help prevent accidental drops, especially when working at heights or in awkward positions.
No specific user reviews or Q&A content were provided for this product to generate additional tips.
9. Warranty and Support
For warranty information, technical support, or service inquiries, please refer to the official UNI-T website or contact your local distributor. Keep your purchase receipt as proof of purchase for warranty claims.
10. UNI-T Brand Introduction
Watch this video to learn more about the UNI-T brand's commitment to quality, precision, and innovation in measurement instruments.
