¿Cómo medir VOLTAJE, CORRIENTE y RESISTENCIA con MULTIMETRO?

¿Cómo medir VOLTAJE, CORRIENTE y RESISTENCIA con MULTIMETRO?

How to Use a Multimeter for Basic Electrical Measurements

Introduction to Multimeters

The multimeter is a crucial tool for diagnosing electronic circuits and verifying proper wiring installations.

Understanding the difference between voltage and current is essential; additional resources are available for clarification.

Parts of a Multimeter

A typical multimeter features a four-digit display, although some models may have three digits.

Key components include the selection knob (for choosing measurement type), test leads (red and black), and specific ports for different measurements:

Black lead usually goes into the COM port.

Red lead connects to either VΩ (voltage, resistance, continuity) or mA/A (current).

Measuring Voltage

To measure voltage, connect the black probe to COM and red probe to VΩ. Set the dial to DC voltage (V with a straight line).

Voltage should be measured in parallel with an energized circuit; example shows measuring LED voltage at 1.8 volts.

When measuring battery voltage, place probes in parallel; an 8.97 reading indicates a discharged 12V battery.

Measuring AC Voltage

For AC voltage measurement, set the multimeter to AC mode (V with wavy line). Example measures household outlet at approximately 120 volts.

Caution is advised when handling probes during measurement to avoid shorts or electric shock.

Measuring Current

To measure DC current, connect the multimeter in series within the circuit; example shows measuring current through an LED at 2.7 mA.

Another example demonstrates measuring current from batteries powering a motor, showing readings around 68 mA.

Advanced Current Measurement Techniques

While using a multimeter for current measurement is possible, it’s not ideal compared to clamp meters designed specifically for this purpose.

How to Measure Current and Continuity with a Multimeter

Setting Up the Multimeter for Current Measurement

The multimeter is set to measure current at 20 amperes, emphasizing the importance of not touching the probes during this process.

It is crucial to note that the multimeter can only measure a maximum of 20 amperes for up to 10 seconds; exceeding this limit may damage the device.

Measuring Current in a Circuit

Probes are connected in series with a fan, which shows a current reading of 0.27 amperes (or 270 milliamperes), demonstrating how to perform current measurements effectively.

Understanding Continuity Testing

The multimeter is switched to continuity mode, indicated by a symbol resembling audio waveforms; this function tests electrical connections between two points.

Continuity testing can verify if cables are functioning properly or if components like fuses on circuit boards are operational.

Practical Applications of Continuity Testing

Users can check connections on stereo connectors and ensure that tracks on circuit boards are intact without breaks.

A normally open push button switch can be tested for functionality using continuity mode, confirming whether it operates correctly.

Features of a Good Multimeter

A quality multimeter should have auto-ranging capabilities, allowing it to automatically adjust its range when measuring voltage or other variables.

The selection knob should feel sturdy and provide resistance when turned; poor-quality meters often have loose knobs that turn too easily.

Additional Functions and Considerations

Good quality probes should be durable, especially at flexible joints where wear occurs frequently; they must also handle sufficient current levels safely.