AstroAI DM130B Digital Multimeter

Introduction

Welcome to the AstroAI DM130B Digital Multimeter. This instrument is designed for measuring AC/DC voltage, AC/DC current, resistance, continuity, diode testing, and battery testing. Please read this manual carefully before operation to ensure safe and accurate use.

This manual may contain information relevant to other AstroAI products. Focus on the DM130B model for specific instructions.

Safety Precautions

⚠️ IMPORTANT SAFETY INFORMATION ⚠️

• Always ensure the multimeter is set to the correct function and range before taking a measurement.
• Never measure voltage in circuits that exceed the maximum voltage rating specified for the instrument.
• Do not touch the test probe tips when they are connected to a circuit.
• Avoid using the multimeter in wet or humid conditions.
• Ensure test leads are in good condition and properly connected.
• ⚡ HIGH VOLTAGE HAZARD: When measuring voltage, especially in AC circuits, exercise extreme caution. Never exceed the CAT rating of the multimeter and test leads.
• When measuring current, always connect the multimeter in series with the load. Never connect it in parallel.
• Replace the battery promptly when the low battery indicator appears.
• Do not attempt to repair the multimeter yourself. Refer servicing to qualified personnel.

Features

• 4000 Counts LCD Display with backlight
• Auto-ranging for Voltage, Current, and Resistance
• AC/DC Voltage Measurement
• AC/DC Current Measurement
• Resistance Measurement
• Continuity Test with Audible Beep ?
• Diode Test
• Battery Test (1.5V, 9V) ?
• Data Hold Function [Hold]
• Relative Value Measurement [REL]
• Low Battery Indicator
• Overload Protection
• CAT III 600V Safety Rating

Getting Started

Understanding the Display

The LCD display shows measurement readings, units, and function indicators. A backlight [?] can be activated for low-light conditions.

• OL: Indicates the reading exceeds the selected range (Over Limit).
• BAT: Indicates the battery is low and needs replacement.
• REL: Indicates the relative measurement mode is active.
• Hz: Indicates frequency measurement (if applicable to model).
• V~: AC Voltage
• V⎓: DC Voltage
• A~: AC Current
• A⎓: DC Current
• Ω: Resistance
• ?: Continuity
• V: Battery Test

Function Dial and Buttons

The rotary dial selects the measurement function. Buttons provide additional features:

• [SELECT]: Cycles through related functions (e.g., AC/DC voltage, AC/DC current).
• [RANGE]: Manually selects the measurement range (if auto-ranging is not desired).
• [HOLD]: Freezes the current reading on the display. Press again to release.
• [REL]: Enters/exits relative measurement mode.
• [BACKLIGHT]: Toggles the display backlight on/off.

Connecting Test Leads

Use the provided test leads. Ensure they are securely plugged into the correct jacks:

• COM: Common jack (always connect the black lead here).
• VΩmA: For voltage, resistance, continuity, diode, and low current measurements (red lead).
• 10A: For high current measurements (red lead). Use this jack only for currents up to 10A.

❗ Ensure test leads are connected to the correct jacks for the measurement being performed. Incorrect connections can damage the multimeter or the circuit under test.

Performing Measurements

DC Voltage (V⎓)

1. Connect the black test lead to the COM jack and the red test lead to the VΩmA jack.
2. Turn the dial to the V⎓ position.
3. Press the [SELECT] button until V⎓ is displayed.
4. Connect the test leads across the component or power source to be measured. The red lead connects to the positive side, and the black lead to the negative side.
5. Read the voltage value on the display.

AC Voltage (V~)

1. Connect the black test lead to the COM jack and the red test lead to the VΩmA jack.
2. Turn the dial to the V~ position.
3. Press the [SELECT] button until V~ is displayed.
4. Connect the test leads across the AC source. Polarity is not critical for AC voltage.
5. Read the voltage value on the display.

DC Current (A⎓)

1. Connect the black test lead to the COM jack.
2. For currents up to 400mA, connect the red test lead to the VΩmA jack. For currents up to 10A, connect the red test lead to the 10A jack.
3. Turn the dial to the A⎓ position.
4. Press the [SELECT] button until A⎓ is displayed.
5. IMPORTANT: Connect the multimeter in series with the circuit. Break the circuit and insert the multimeter.
6. Read the current value on the display.
7. ❗ After measurement, return the red lead to the VΩmA jack and the dial to a voltage setting to avoid damage when measuring voltage next time.

AC Current (A~)

1. Follow steps 1-4 for DC Current measurement, but select the A~ function using the [SELECT] button.
2. Connect the multimeter in series with the AC circuit.
3. Read the current value on the display.
4. ❗ After measurement, return the red lead to the VΩmA jack and the dial to a voltage setting.

Resistance (Ω)

1. Connect the black test lead to the COM jack and the red test lead to the VΩmA jack.
2. Turn the dial to the Ω position.
3. Connect the test leads across the resistor or component to be measured. Ensure the circuit is de-energized.
4. Read the resistance value on the display. If the display shows "OL", the resistance is higher than the selected range.

Continuity Test (?)

1. Connect the black test lead to the COM jack and the red test lead to the VΩmA jack.
2. Turn the dial to the ? (Continuity) position.
3. Connect the test leads across the component to be tested.
4. If the resistance is very low (typically below 30 Ω), the multimeter will emit an audible beep ?.

Diode Test

1. Connect the black test lead to the COM jack and the red test lead to the VΩmA jack.
2. Turn the dial to the Diode symbol (often near Continuity).
3. Connect the red lead to the anode and the black lead to the cathode of the diode.
4. A forward voltage drop (typically 0.4V to 0.9V) will be displayed for a good diode. If the display shows "OL" or a very low voltage, the diode may be faulty.

Battery Test (V)

1. Connect the black test lead to the COM jack and the red test lead to the VΩmA jack.
2. Turn the dial to the V (Battery Test) position.
3. Press the [SELECT] button to choose the battery type (e.g., 1.5V, 9V).
4. Connect the test leads to the battery terminals (red to positive, black to negative).
5. Read the battery voltage on the display. Compare it to the expected voltage for its type.

Specifications

Specifications are subject to change without notice.

Troubleshooting

Warranty and Support

AstroAI offers a limited warranty for its products. For detailed warranty information or technical support, please visit the official AstroAI website or contact their customer service.

Website: https://www.astroai.com