1. Introduction
This manual provides detailed instructions for the safe and proper use of the Mastech MS2108 Digital Clamp Meter. This portable, professional measuring instrument features an LCD with backlight for easy reading and a 'single-hand operation' design for the range switch. It offers overload protection and low battery indication, making it an ideal multi-function instrument for industrial, mining, and vehicle maintenance electrical engineers.
2. Safety Information
Always observe local and national safety codes. Use personal protective equipment (PPE) as required. Failure to follow safety precautions can result in injury or damage to the meter.
- Conforms to IEC61010-1 & IEC61010-032 standard.
- Double insulation (protection class 600V CAT III and pollution degree 2).
- Do not use the meter if it or the test leads appear damaged.
- Ensure the function switch is in the correct position before making measurements.
- Do not exceed the maximum input limits for any range.
- Exercise extreme caution when working with live electrical circuits.
3. Key Features
- True RMS measurement for accurate readings on non-sinusoidal waveforms.
- Inrush current function for measuring motor starting current.
- Over-molding rubber case for enhanced durability and protection.
- Clamp-on frequency function.
- Auto range/manual range selection.
- Data hold function to freeze readings on the display.
- Maximum/minimum value measurement.
- Auto power off to conserve battery life.
- Backlight for improved visibility in low-light conditions.
- Jaw lighting for illuminating the measurement area.
- Continuity checking with buzzer and Diode test.
4. Product Overview
Front view of the Mastech MS2108 Digital Clamp Meter, showing the display, function dial, buttons, and clamp jaw.
Angled view of the Mastech MS2108 Digital Clamp Meter, highlighting its ergonomic design and compact size.
Close-up view of the control panel on the Mastech MS2108, detailing the function dial, SEL, MIN/MAX, RAN, Hz/%, and B.L. HOLD buttons.
Included test leads for voltage and resistance measurements, along with protective caps.
Diagram illustrating key features and specifications of the MS2108, including jaw size, voltage, current, and various measurement functions.
5. Setup and Battery Installation
5.1 Battery Installation
The MS2108 requires 3 x 1.5V AAA batteries (not included). To install:
- Ensure the meter is turned OFF.
- Locate the battery compartment cover on the back of the meter.
- Use a screwdriver to open the battery compartment.
- Insert three AAA batteries, observing the correct polarity (+/-) as indicated inside the compartment.
- Replace the battery compartment cover and secure it with the screw.
5.2 Connecting Test Leads
For voltage, resistance, capacitance, frequency (from test terminal), continuity, and diode measurements, connect the test leads:
- Insert the red test lead into the 'INPUT' jack.
- Insert the black test lead into the 'COM' (common) jack.
6. Operating Instructions
6.1 Function Dial
Rotate the central dial to select the desired measurement function:
- OFF: Turns the meter off.
- V~: AC Voltage measurement.
- V-: DC Voltage measurement.
- A~: AC Current measurement (using clamp).
- A-: DC Current measurement (using clamp).
- Ω K Å: Resistance, Continuity, Diode, Capacitance measurement. Use the 'SEL' button to cycle through these functions.
- Hz%: Frequency and Duty Cycle measurement.
6.2 Button Functions
- SEL (Yellow Button): Selects sub-functions within a main dial position (e.g., AC/DC, Ohm/Diode/Continuity).
- MIN/MAX: Toggles between minimum and maximum recorded values during a measurement session.
- RAN: Toggles between auto-ranging and manual ranging. In manual range, press repeatedly to cycle through ranges.
- Hz/%: When in Voltage or Current mode, press to display frequency or duty cycle.
- B.L. HOLD: Short press to activate/deactivate data hold (freezes the current reading). Long press (2 seconds) to turn the backlight ON/OFF.
- Inrush: Press this button when the dial is in an AC/DC current position to measure inrush current.
6.3 Measurement Procedures
AC/DC Current Measurement (Clamp):
- Turn the function dial to the A~ (AC) or A- (DC) position.
- Open the clamp jaw and enclose a single conductor. Ensure the jaw is fully closed.
- Read the current value on the display. For DC current, observe the polarity.
AC/DC Voltage Measurement:
- Connect the test leads to the 'INPUT' and 'COM' jacks.
- Turn the function dial to V~ (AC) or V- (DC).
- Connect the test probes in parallel to the circuit or component under test.
- Read the voltage value on the display.
Resistance, Continuity, Diode, Capacitance Measurement:
- Connect the test leads.
- Turn the function dial to the Ω K Å position.
- Press the 'SEL' button to cycle through Resistance (Ω), Continuity (K), Diode (Å), and Capacitance (uF) functions.
- Connect the test probes to the component. For continuity, a buzzer will sound if resistance is below approximately 50Ω.
Inrush Current Measurement:
- Set the function dial to A~ or A-.
- Press the 'Inrush' button. The display will show 'Inr'.
- Open the clamp jaw and enclose the conductor of the device you wish to test the inrush current for (e.g., motor, compressor).
- Activate the device. The meter will capture and display the peak inrush current.
7. Maintenance
7.1 Cleaning
Wipe the meter's case with a damp cloth and mild detergent. Do not use abrasives or solvents. Keep the input terminals free of dirt or debris.
7.2 Battery Replacement
When the battery symbol appears on the display, replace the batteries as described in Section 5.1. Remove batteries if the meter is not used for extended periods.
7.3 Storage
Store the meter in a cool, dry place, away from direct sunlight and extreme temperatures. If storing for a long period, remove the batteries.
8. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No display or dim display | Dead or low batteries | Replace batteries (Section 5.1) |
| Incorrect readings | Incorrect function selected; Test leads not properly connected; Exceeding input limits | Select correct function; Ensure leads are fully inserted; Do not exceed specified limits |
| "OL" (Overload) displayed | Input value exceeds selected range | Switch to a higher range (if in manual mode) or ensure input is within meter's capabilities |
| No continuity buzzer | Resistance too high; Function not set to continuity | Ensure circuit is closed and resistance is low; Press SEL to select continuity mode |
9. Technical Specifications
The following table details the technical specifications for the Mastech MS2108 Digital Clamp Meter:
Comprehensive technical specifications table for the Mastech MS2108 and MS2108A models, detailing measurement ranges, accuracy, and general features.
- Display: 6600 counts
- MAX. Diameter for conductor: 26mm
- Power: 1.5V (AAA) x 3
- Size: 208mm x 78mm x 35 mm
- Weight: Approximately 1.1 Pounds (including batteries)
10. Warranty and Support
Mastech products are designed for reliability and performance. This product is covered by a manufacturer's warranty against defects in materials and workmanship. For specific warranty terms and conditions, please refer to the warranty card included with your product or contact Mastech customer support.
For technical assistance, troubleshooting, or service inquiries, please contact Mastech customer support through their official website or authorized service centers. Please have your model number (MS2108) and purchase information ready when contacting support.
