Why can the resistance of a resistor be measured while it is in a circuit?

Why can the resistance of a resistor be measured while it is in a circuit?

Normally, it cannot be. In simple terms, you will also measure the other components of the circuit, which will result in an inaccurate measure of resistance. For some circuits, the arrangement of the other components works, you will get an accurate measurement, and however, this is not always true.

One cannot measure the resistance of a resistor in circuit because there are other paths that will affect the measurement. For example, another resistor located elsewhere in the circuit may be in parallel with the resistor in question.

Ohmmeters work by sending a constant known current into a circuit and measuring the voltage that fell on the probes.

If you do not disconnect the component to be measured, the current is divided into all available circuit paths.

a result, less current than the calibrated one will flow in the resistor. As a result, less voltage will drop across the resistor and the ohmmeter will interpret this as a lower resistance, based on the ohm’s law.

Resistance is a static value. The ohmmeter resistance measuring equipment only works on non-accelerated circuits.

The ohmmeter itself is spoiled if used in active circuits.

There are some ways specified in this way only. We cannot do what we want. Certain procedures must be followed to achieve our objective or result.

It can but the measurement response or reading provided is inaccurate!

Because it is typical to measure other parameters present and parallel to this resistance, which gives a false reading.

The regular ohmmeter has low impedance that adds a load effect…

to measure the resistance, the pump meter in fact a small amount of current and voltage known to measure resistance using ohm’s law!

It may be possible or not to measure a circuit resistance. It depends on what can actually be in parallel.

It also assumes that the circuit is not powered. When powered, normal operating voltages distort readings and can cause damage (especially if you use an analog meter.)

On the other hand, you must apply a voltage to measure voltages. This (and the display of waveforms on an oscilloscope) is the main method of troubleshooting.

Be very careful when working with live circuits.

 

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