Measuring voltage involves using a device, typically a multimeter, to determine the electrical potential difference between two points in a circuit. Here's a breakdown of how to do it:
The basics of using a multimeter to measure voltage:
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Set up the Multimeter: Ensure your multimeter is set to voltage (V) mode. If it's an autoranging multimeter, it will automatically select the appropriate range. If not, select a voltage range higher than what you expect to measure.
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Connect the Probes:
- Plug the black probe into the COM (common) port.
- Plug the red probe into the V (voltage) port.
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Apply the Probes:
- Touch the probes to the two points in the circuit where you want to measure the voltage. According to the provided reference, when measuring the voltage across an LED, you can "touch one probe to each leg of the LED."
- Ensure good contact.
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Read the Display: The multimeter will display the voltage reading.
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Polarity: According to the provided reference, if you reverse the probes when measuring voltage, you will get a negative voltage reading. This indicates the polarity. The red probe is typically connected to the positive (+) side, and the black probe to the negative (-) side.
Example:
Imagine you're measuring the voltage across an LED (Light Emitting Diode).
- Set your multimeter to voltage (DC voltage if it's a DC circuit).
- Touch the red probe to the positive leg of the LED.
- Touch the black probe to the negative leg of the LED.
- Read the voltage displayed on the multimeter. The reference example indicates a reading of about 2 volts when measuring an LED.
- If you reverse the probes, the reading will be approximately -2 volts.
