GVDA Smart Multimeter User Manual

Introduction

This manual provides detailed instructions for the safe and effective use of your GVDA Smart Digital Multimeter, models GD138A and GD138B. This intelligent true RMS digital multimeter features full functionality, including gear display and an analog bar multiple display, with a sampling speed of 3 times per second. Please read this manual carefully before operation and retain it for future reference.

Safety Instructions

The meter conforms to IEC61010-1 CAT.III 600V overvoltage safety standard and pollution level 2. To avoid possible electric shock or personal injury, please observe the following specifications:

⚠ Warning:

• Read this manual carefully and pay special attention to safety warning information before using the meter.
• Operate the meter according to the manual; otherwise, the protection function provided by the instrument may be damaged or weakened.
• Take special care when measuring values that exceed 60V DC, 30V AC RMS, or 42V. These voltages pose a risk of electric shock.
• Do not measure voltage higher than the rated value between terminals or between terminals and ground.
• Measure a known voltage to check if the meter works normally. If it is not normal or damaged, do not use it again.
• Before using the meter, check for cracks or damaged plastic parts in the instrument shell. If found, do not use it again.
• Before using the meter, check if the probe is cracked or damaged. If so, replace the probe with one of the same model and electrical specification.
• Use the meter according to the measurement category, voltage, or current rating specified in the meter or manual.
• Observe local and national safety regulations. Wear personal protective equipment (such as approved rubber gloves, masks, and flame-retardant clothing) to prevent injury from electric shock and electric arc when dangerous live conductors are exposed.
• When the "battery" symbol is displayed, replace the battery promptly to prevent measurement error.
• Do not use the meter in environments with explosive gas, vapor, or high humidity.
• When using the probe, hold your fingers behind the probe finger guard.
• When measuring, connect the null or ground wire first, then the live wire; when disconnecting, disconnect the live wire first, then the null or ground wire.
• Remove the probe from the meter before opening the case or battery cover. Do not use the meter when disassembled or with the battery cover open.
• The meter can only be used with the provided probes that meet safety standards. If a probe is damaged and needs replacement, use a probe of the same model and electrical specification.

⚠ Caution:

• Operation may cause damage to the meter or equipment.

Product Overview

The GVDA Smart Multimeter is designed for intelligent and professional electrical measurements. Below is an illustration of its main components:

Key Components:

• Display: Digital and analog bar multiple display for measurement readings.
• Power Button: Turns the device on/off.
• FUNC Button: Used for gear selection and switching between intelligent and manual modes.
• Hold Button: Toggles data hold function.
• Flashlight Button: Activates/deactivates the built-in flashlight.
• Backlight Button: Toggles display backlight.
• Input Jack: For connecting the red test lead.
• COM Jack: For connecting the black test lead.
• NCV Sensor Area: Used for non-contact AC voltage detection.
• Warning Indicator: Lights up during certain detection modes (e.g., NCV, Live).

Setup

Battery Installation

The multimeter requires 2 x 1.5V AAA batteries (not included). Follow these steps to install or replace batteries:

1. Ensure the multimeter is powered off and disconnect all test probes.
2. Locate the battery cover on the back of the device.
3. Unscrew the screw fixing the battery cover and remove the cover.
4. Insert two new 1.5V AAA batteries, observing the correct polarity (+/-).
5. Replace the battery cover and secure it with the screw.

Note: Replace batteries immediately when the low battery indicator appears on the display to ensure accurate readings.

Operating Instructions

Power On/Off

• Press and hold the Power button for approximately 2 seconds to turn the multimeter on or off.

Gear Selection (Measurement Modes)

• The multimeter powers on in intelligent (AUTO) measurement mode by default.
• To enter manual mode, press the FUNC key. Subsequent presses will cycle through available measurement functions.
• To return to intelligent (AUTO) measurement mode, press and hold the FUNC key for approximately 2 seconds.

Smart (AUTO) Measurement

This is the default mode upon power-on. In this mode, the meter can automatically identify and measure DC voltage, AC voltage, resistance, and continuity.

1. Power on the meter. It will display "Auto" and enter intelligent measurement mode.
2. Insert the red test lead into the "INPUT" jack and the black test lead into the "COM" jack.
3. Contact the probes with both ends of the circuit or component to be measured. The meter will automatically recognize the signal.
4. Read the measurement results from the display.

Note: The minimum measurable voltage in this mode is 0.8V.

Professional Measurement Modes

AC/DC Voltage Measurement

1. Power on the meter.
2. Press the FUNC key to select the "V" (AC Voltage) or "V" (DC Voltage) gear.
3. Insert the red test lead into "INPUT" and the black test lead into "COM".
4. Contact the probes with both ends of the power supply to be measured (in parallel).
5. Read the results from the display.

Resistance Measurement

1. Power on the meter.
2. Press the FUNC key to select the "Ω" (Resistance) gear.
3. Insert the red test lead into "INPUT" and the black test lead into "COM".
4. Contact the probes with both ends of the resistance to be measured (in parallel).
5. Read the results from the display.

Continuity Test

1. Power on the meter.
2. Press the FUNC key to select the "))" (Continuity) gear.
3. Insert the red test lead into "INPUT" and the black test lead into "COM".
4. Contact the probes with both ends of the resistance or circuit to be tested.
5. If the resistance value is less than 50 Ω, the buzzer will sound and the alarm indicator will illuminate.
6. Read the results from the display.

Frequency Measurement

1. Power on the meter.
2. Press the FUNC key to select the "Hz" (Frequency) gear.
3. Insert the red test lead into "INPUT" and the black test lead into "COM".
4. Contact the probes with both ends of the power supply to be measured.
5. Read the results from the display.

Non-Contact AC Voltage Detection (NCV)

1. Power on the meter.
2. Press the FUNC key to select the "NCV" gear.
3. Gradually bring the NCV sensor area of the meter close to the conductor.
4. If a weak electric field signal is detected, "---L" will be displayed, the buzzer will sound slowly, and the green light will turn on.
5. If a strong electric field signal is detected, "---H" will be displayed, the buzzer will sound quickly, and the red light will turn on.

Live Wire Detecting

1. Power on the meter.
2. Press the FUNC key to select the "Live" gear.
3. Insert the red test lead into "INPUT" and remove the black test lead.
4. Use the red probe to contact the conductor.
5. If a weak electric field signal is detected, "---L" will be displayed, the buzzer will sound slowly, and the green light will turn on.
6. If a strong electric field signal is detected, "---H" will be displayed, the buzzer will sound quickly, and the red light will turn on.

Data Hold

• Press the Hold key to turn on or off data holding.
• Note: This function is invalid in NCV / Live modes.

Flashlight

• Press and hold the Flashlight key for approximately 2 seconds to turn the flashlight on or off.

Backlight

• Press the Backlight key to turn the display backlight on or off.
• Note: VA display models may not have this function.

Auto Power Off

• After power on, auto power off is enabled by default, indicated by the "battery" symbol.
• If there is no key operation for about 15 minutes, the meter will automatically shut down to save battery energy.
• To disable auto power off, press and hold the FUNC key while turning on the meter. The "battery" symbol will not be displayed.

Specifications

General Technical Specifications

• Environment Condition of Use: CAT. III 600V, Pollution level 2, Altitude < 2000m
• Working Temperature and Humidity: 0~40°C (<80% RH, <10°C non-condensing)
• Storage Temperature and Humidity: -10~60°C (<70% RH, remove the battery)
• Temperature Coefficient: 0.1 x accuracy/°C (<18°C or >28°C)
• Max. Voltage between terminals and earth ground: 600V
• Sampling Rate: Approximately 3 times/second
• Display: 4000 counts
• Over Range Indication: "OL"
• Low Battery Indication: "battery" symbol will be displayed.
• Input Polarity Indication: Displays "-".
• Power Requirement: 2 x 1.5V AAA batteries.
• Dimensions: 126mm x 65mm x 20mm
• Product Weight: 107g

Accuracy Specifications

The accuracy applies within one year after calibration. Reference condition: environment temperature 18°C to 28°C, relative humidity no more than 80%. Accuracy: ± (% reading + word).

DC Voltage

AC Voltage

Impedance: Approx. 10MΩ
Frequency Response: 40Hz-1kHz: TRMS

Resistance

Overload protection: 250V

Continuity

• Approx. 50Ω, Buzzer will sound and the indicator light will be on.

Frequency

Overload protection: 250V

Capacitance (GD138B Only)

Package Contents

• 1x GVDA Smart Multimeter (GD138A or GD138B)
• 1x Pair of Test Leads (Pen cable)
• 1x Cloth Bag
• 1x User Manual (this document)
• 1x Retail Box

Maintenance

Cleaning

To clean the meter, follow these steps:

1. Turn off the meter power and remove the probes.
2. Wipe the case with a damp cloth or mild detergent. Do not use abrasives or solvents.
3. Wipe the contacts in each input socket with a clean swab soaked in alcohol.

Warning: Always keep the inside of the meter clean and dry to prevent electric shock or damage to the meter.

Battery Replacement

Refer to the "Battery Installation" section under Setup for detailed instructions on replacing the batteries.

Warning: To avoid electric shock or personal injury caused by wrong readings, replace the battery immediately when the battery is low. Do not discharge the battery by shorting it or reversing its polarity. To operate and maintain the meter safely, remove the battery if not used for a long time to prevent battery leakage from damaging the product.

Troubleshooting

If you encounter issues with your GVDA Smart Multimeter, please refer to the following common troubleshooting steps:

• No Display / Meter Does Not Turn On:
  • Check if the batteries are correctly installed and have sufficient charge. Replace with new batteries if necessary.
  • Ensure the power button is pressed and held for the required duration (approx. 2 seconds).
• Incorrect or Unstable Readings:
  • Verify that the test leads are securely connected to the correct input jacks ("INPUT" and "COM").
  • Ensure the test probes are making good contact with the circuit or component.
  • Confirm that the correct measurement mode (gear) is selected for the type of measurement being performed.
  • Check for any damage to the test leads or probes. Replace if damaged.
  • Ensure the operating environment is within the specified temperature and humidity ranges.
• Buzzer Not Sounding During Continuity Test:
  • Ensure the meter is in Continuity mode ("))").
  • Verify that the resistance of the circuit being tested is below 50 Ω.
• NCV / Live Detection Not Working:
  • Ensure the meter is in the correct NCV or Live mode.
  • For Live detection, ensure only the red probe is connected to the "INPUT" jack.
  • Ensure the NCV sensor area is brought sufficiently close to the conductor.

For further assistance, please refer to the complete user manual PDF or contact customer support.

Warranty and Support

For detailed warranty information and customer support, please refer to the official product documentation or contact your retailer. A comprehensive user manual in PDF format is available for download:

Download User Manual (PDF)