MASTECH MS2138, MS2138R, MS2160 Series AC/DC Digital Clamp Meter Instruction Manual

1. Introduction

Thank you for choosing the MASTECH MS2138, MS2138R, or MS2160 Series AC/DC Digital Clamp Meter. These high-performance instruments are designed for electrical and electronic engineers, offering precise measurements for a wide range of applications. They are suitable for testing and maintenance in various fields including universities, vocational colleges, manufacturing, petroleum, national defense, electricity, power supply systems, and circuit power equipment.

These clamp meters are ideal for monitoring the operation status of on-site equipment such as transmission and distribution cables, transformers, motors, distribution cabinets, fans, pumps, and for testing static current in automotive engines or chip operating current.

2. Safety Information

Please read and understand all safety information before operating this instrument. Failure to follow these instructions could result in electric shock, fire, or serious injury.

• Always adhere to local and national safety codes.
• Do not use the meter if it appears damaged or if the insulation on the test leads is compromised.
• Ensure the rotary switch is in the correct position for the desired measurement before connecting to the circuit.
• Do not apply voltage or current that exceeds the maximum rated values for the meter.
• Be cautious when working with voltages above 30V AC RMS, 42V peak, or 60V DC, as these pose a shock hazard.
• Replace batteries immediately when the low battery indicator appears to ensure accurate readings.
• This device is rated CAT III 600V, indicating its suitability for measurements in distribution boards, circuit breakers, wiring, including cables, bus-bars, junction boxes, switches, socket outlets in the fixed installation, and industrial use with permanent connection to the fixed installation.

3. Product Overview

The MASTECH MS2138, MS2138R, and MS2160 series are compact, handheld digital clamp meters designed for professional use. They feature a 4000-count digital LCD display for clear readings and are equipped with various functions for comprehensive electrical testing.

3.1 Key Features

• Display: 4000 counts with analog bar LCD display.
• Ranging: Auto and Manual Ranging.
• Auto Power Off: Automatically turns off after 15 minutes of inactivity to conserve battery.
• Data Hold: Freezes the current reading on the display.
• Relative Measurement: Measures the difference between a stored reference value and the current reading.
• Low Battery Display: Indicates when batteries need replacement.
• Display Backlight: For improved visibility in dimly lit environments.
• Work Light: Illuminates the measurement area.
• Overrange Protection: Provided for all ranges.

3.2 Model Specific Features

• MS2138 / MS2138R: Jaw Opening Φ40mm (1.6 inches). Diode Open Voltage 2.8V. Continuity Buzzer <50±2Ω.
• MS2160: Jaw Opening Φ24mm (0.9 inches). Non-Contact Voltage (NCV) Detector. Diode Open Voltage 3.2V. Continuity Buzzer <50Ω.

3.3 Components and Controls

Refer to the diagrams below for an overview of the clamp meter's components and controls.

Common Controls:

• Rotary Switch: Selects the measurement function (e.g., ACV, DCV, ACA, DCA, Ohms, Hz, Capacitance, Diode, Continuity).
• RANGE Button: Switches between auto-ranging and manual ranging.
• REL Button: Activates relative measurement mode.
• Hz/% Button: Selects frequency or duty cycle measurement.
• HOLD Button: Freezes the current display reading.
• FUNC Button (MS2138/R): Toggles between different functions within a single rotary switch position (e.g., AC/DC current).
• SEL Button (MS2160): Toggles between different functions within a single rotary switch position.
• NCV Button (MS2160): Activates Non-Contact Voltage detection.
• Backlight/Work Light Button: Activates the display backlight and/or work light.

4. Specifications

The following table details the technical specifications for the MS2160 model. Specifications for MS2138/MS2138R are similar for common functions, with differences noted in the Product Overview section.

4.1 General Specifications

• Maximum Voltage (Terminals to Earth Ground): 600V DC or 600V RMS AC
• Operating Altitude: Max. 2000 meters (7000 ft.)
• Polarity Indication: Automatic; '-' for negative polarity.
• Overrange Indication: '0L' or '-0L'
• Converter Rate: 3 times/sec; Bar graph: 30 times/sec.
• Unit Indication: Function and unit.
• Operating Power: 3 × 1.5V AAA batteries
• Temperature Factor: < 0.1 × Accuracy /°C
• Operating Temperature: 0°C to 40°C (32°F to 104°F)
• Storage Temperature: -10°C to 50°C (10°F to 122°F)
• Dimensions:
  • MS2138/R: 225 × 86 × 33mm
  • MS2160: 195 × 80 × 45mm
• Weight:
  • MS2160: 195g (0.43lb)
• Safety Rating: CAT III 600V (CE / ETL / RoHS certified)

5. Setup

5.1 Unpacking and Inspection

Carefully unpack your new clamp meter and check for any signs of damage. Ensure all accessories are present:

• Digital Clamp Meter (MS2138, MS2138R, or MS2160)
• Test Leads
• K-type Thermocouple (for MS2160, and potentially MS2138/R if included in specific package)
• Carry Bag
• User's Manual

5.2 Battery Installation

The clamp meter requires three 1.5V AAA batteries (not included). To install or replace batteries:

1. Ensure the meter is turned OFF and disconnect any test leads from the input terminals.
2. Locate the battery compartment cover on the back of the meter.
3. Use a screwdriver to loosen the screw(s) on the battery cover and remove the cover.
4. Insert three new 1.5V AAA batteries, observing the correct polarity (+ and -).
5. Replace the battery cover and tighten the screw(s).

5.3 Connecting Test Leads

For voltage, resistance, capacitance, frequency (via leads), diode, and continuity measurements, connect the test leads:

• Insert the black test lead into the 'COM' (Common) input jack.
• Insert the red test lead into the 'VΩHz' (Voltage, Resistance, Frequency) input jack.

6. Operating Instructions

This section provides general instructions for using the clamp meter's various functions. Always ensure the meter is set to the correct function and range before making any measurements.

6.1 Power On/Off

Turn the rotary switch from the 'OFF' position to any desired measurement function to power on the meter. To power off, turn the rotary switch back to 'OFF'. The meter also features an auto power off function after 15 minutes of inactivity.

6.2 AC/DC Current Measurement (Clamp)

To measure AC or DC current using the clamp jaw:

1. Turn the rotary switch to the 'ACA' (AC Current) or 'DCA' (DC Current) position. For MS2138/R, use the 'FUNC' button to switch between AC and DC. For MS2160, use the 'SEL' button.
2. Open the clamp jaw by pressing the trigger.
3. Enclose only one conductor (wire) with the clamp jaw. Ensure the jaw is completely closed.
4. Read the current value on the display.

6.3 Voltage Measurement (AC/DC)

To measure AC or DC voltage:

1. Connect the test leads as described in Section 5.3.
2. Turn the rotary switch to the 'ACV' (AC Voltage) or 'DCV' (DC Voltage) position. For MS2138/R, use the 'FUNC' button to switch between AC and DC. For MS2160, use the 'SEL' button.
3. Connect the test probes across the circuit or component to be measured.
4. Read the voltage value on the display.

6.4 Resistance Measurement

To measure resistance:

1. Connect the test leads as described in Section 5.3.
2. Turn the rotary switch to the 'Ω' (Resistance) position.
3. Ensure the circuit is de-energized before connecting the test probes across the component.
4. Read the resistance value on the display.

6.5 Continuity Test

To perform a continuity test:

1. Connect the test leads as described in Section 5.3.
2. Turn the rotary switch to the 'Ω' (Resistance) position and use the 'FUNC' or 'SEL' button to select continuity mode (indicated by a buzzer icon).
3. Ensure the circuit is de-energized.
4. Connect the test probes across the component. An audible beep indicates continuity (resistance below approximately 50Ω).

6.6 Diode Test

To test a diode:

1. Connect the test leads as described in Section 5.3.
2. Turn the rotary switch to the 'Ω' (Resistance) position and use the 'FUNC' or 'SEL' button to select diode mode (indicated by a diode symbol).
3. Ensure the circuit is de-energized.
4. Connect the red test lead to the anode and the black test lead to the cathode of the diode. The display will show the forward voltage drop. Reverse the leads; the display should show 'OL' (open loop) for a good diode.

6.7 Capacitance Measurement

To measure capacitance:

1. Connect the test leads as described in Section 5.3.
2. Turn the rotary switch to the 'Capacitance' position (indicated by a capacitor symbol).
3. Ensure the capacitor is fully discharged before connecting the test probes.
4. Connect the test probes across the capacitor.
5. Read the capacitance value on the display.

6.8 Frequency and Duty Cycle Measurement

To measure frequency or duty cycle:

1. Connect the test leads as described in Section 5.3, or use the clamp for current frequency.
2. Turn the rotary switch to the 'Hz' position.
3. Press the 'Hz/%' button to toggle between frequency (Hz) and duty cycle (%).
4. Connect the test probes to the signal source or clamp the conductor.
5. Read the frequency or duty cycle value on the display.

6.9 Non-Contact Voltage (NCV) Detection (MS2160 only)

The MS2160 model features NCV detection to identify live AC voltage without direct contact:

1. Turn the rotary switch to the 'NCV' position or press the 'NCV' button.
2. Move the top of the clamp meter near the conductor or outlet.
3. The meter will emit an audible beep and/or visual indication (e.g., LED light) if AC voltage is detected.

6.10 Temperature Measurement (MS2160 only)

To measure temperature using the K-type thermocouple:

1. Turn the rotary switch to the '°C/°F' position.
2. Connect the K-type thermocouple to the input jacks, observing polarity.
3. Place the thermocouple probe on or near the object whose temperature is to be measured.
4. Read the temperature value on the display. Use the 'SEL' button to switch between Celsius and Fahrenheit.

6.11 Data Hold and Relative Measurement

• Data Hold: Press the 'HOLD' button to freeze the current reading on the display. Press it again to release.
• Relative Measurement: Press the 'REL' button to store the current reading as a reference. Subsequent measurements will show the difference from this reference value. Press 'REL' again to exit this mode.

6.12 Work Light and Backlight

Press the dedicated button (often combined with 'HOLD' or 'LIGHT' function) to activate the display backlight for better visibility in low light. Some models also include a work light to illuminate the measurement area.

Video 1: MASTECH MS2138R AC/DC Clamp Meter Features Overview

7. Maintenance

7.1 Cleaning

To clean the meter, wipe the case with a damp cloth and a mild detergent. Do not use abrasives or solvents. Ensure the meter is completely dry before use.

7.2 Battery Replacement

Replace the batteries when the low battery indicator appears on the display. Refer to Section 5.2 for detailed instructions on battery installation.

7.3 Storage

When the meter is not in use for an extended period, remove the batteries to prevent leakage. Store the meter in its carry bag in a cool, dry place, away from direct sunlight and extreme temperatures.

8. Troubleshooting

9. User Tips

• For the most accurate current measurements with the clamp, ensure only one conductor passes through the jaw. Clamping around multiple conductors carrying current in opposite directions will result in a zero or incorrect reading.
• Always start with the highest range when measuring an unknown value to prevent overloading the meter.
• Utilize the 'HOLD' function when taking measurements in hard-to-reach areas where the display might not be visible during the measurement.
• The 'REL' (Relative) function is useful for nulling out test lead resistance or comparing measurements against a baseline.

10. Warranty and Support

MASTECH products are designed for reliability and performance. For specific warranty details and technical support, please refer to the warranty card included with your product or contact your local MASTECH distributor. Keep your purchase receipt as proof of purchase for any warranty claims.