Ohmmeter vs Multimeter – Which is Best? A Complete Guide:

It is important to know that a variety of electric meters comes to determine different units of electricity, so whether you are troubleshooting or repairing, you just need the right type. Knowing what type of units are involved and how they work is vital for someone who works with electronics. The unit which is measured most frequently is resistance, and for this purpose, an ohmmeter can prove useful. Whereas for the determination of current, voltage, temperature, and capacitance, a multimeter (meter with multi efficiencies) performs best.

Ohmmeter vs multimeter:

Both ohmmeter and multimeter are standard gadgets electricians use to determine electrical resistance within circuits. Regrettably, most people cannot identify the difference between an ohmmeter and a multimeter, yet, they used to perform tasks with them. We will attempt to explain these devices to you in this article.

What is an ohm-meter?

An ohm-meter is a handy electronic device designed to examine the resistance in a circuit, the circuit’s components, and its continuity. An ohm (or Ohms) is an electrical unit used to measure resistance. Resistance is the barrier that a body creates to prevent current flow in an electrical circuit. The ohmmeter can be arranged either in series or parallel. If you arrange it in parallel, the resistance will rise along with the current.

While arranged in series, the current is reduced by increasing resistance. Ohmmeters are available in three different variations: micro ohmmeter (for the measurement of small resistance), milli (for the accurate measurement of low resistance), and mega-ohmmeter (for high resistance). Remember that an ohmmeter structures circuits by itself, therefore it is not eligible for collected circuits. For the determination of resistance within a circuit, turn off the power and then observe the reading. Usually, the ohmmeter comprises:
● Battery source,
● Meter for current,
● Current restraining resistor.

What is the other name of an ohmmeter?

An ohmmeter can also be referred to as a micro-ohmmeter.

Voltmeter:

It is the device used to examine variation between the electrodes of a circuit. By attaching the voltmeter to the circuit in parallel, the voltage decreases. Additionally, the high internal resistance combined with the slight current makes the voltage meter more accurate at checking potential changes. Voltmeters will not be accurate with low
internal resistance, since current flows freely.

Ammeter:

This instrument is utilized to test the alternate or direct current within a circuit. That is the movement of charges or charged particles throughout the conductor. The ammeter will give more accurate results if attached in series, as in series, low resistance will allow more current to stream.

What’s the difference between an ohm-meter and a voltmeter?

Ohmmeters are used to test high resistance values, while voltage meters determine the voltage across a circuit.

Multimeter:

A single instrument called a multimeter works by testing amperes, temperatures, AC/DC voltages, ohms, and many more, and due to these properties also referred to as a volt-ohm-milli-ammeter. Advanced multimeter offers the measurement of other parameters like circuit continuity, frequency, duty cycle, capacitance, etc. For the testing of the desired parameter, It is necessary to set the proper range before obtaining a reading. Attach test probes to the circuit or instrument with which you will be measuring.

Is a multimeter the same as an ohmmeter?

A multimeter can work in place of an ohmmeter. An ohm-meter only measures resistance. While a multi-meter can perform various tasks such as current, temperature, voltage, etc. Along with resistance measurement.

What are the similarities between a multimeter and an ohmmeter?

Both multi-meter and ohm-meter can determine resistance as well as continuity of circuits

What are the differences between multi-meter vs ohm-meter?

Key Differences between multi-meter vs ohm-meter:

Multi-Meter
Ohm-Meter

1- Multi-meters may determine
other properties besides
resistance such as ampere,
capacitance, temperature,
voltage, etc.

2- Digital multi-meters give more
accurate results.

3- Multi-meter costs are high

because of the variety of

functions.

1- The main purpose of the
ohm-meter is to determine
the internal resistance and
continuity of a circuit only.

2- Ohm-meters are only
available in analog format, so
the results can show
fluctuations in reading.

3- Ohmmeters cost less because
they have inferior
performance.

Working:

How to use an Ohm-meter:

Typical analog ohmmeters are composed of a needle and a pair of test leads. The meter will either deflect to the right or left in reaction to the current flowing through the circuit. Generally, the left side represents the highest resistance and little current whereas the right side displays small resistance with excessive current.

How to use a multi-meter? Working of multimeter:

The most common kind of multimeter is the digital multimeter (DMM), although other types are available as well. This device features a selector switch, which enables you to select the electrical characteristics to be measured. It also features an analog to digital converter, along with a digital display to display the measurements. The unknown resistor is connected to a current source and a small current is infused into it. Note the voltage drop across the unknown resistors.

After this all has been done, Ohm’s Law is applied and the resistance is shown on the screen. The meter reads the current flowing in the circuit by deflecting the pointer within its frame. There is a battery inside the instrument which provides the power for the current. A milliammeter connected in series with the circuit converts the reading into its resistance using Ohm’s Law.

Types of ohm-meter:

Series type ohm-meter:

Ohmmeter of this kind determines the resistance only when the component to be measured is attached in series with the meter. This component, by adding resistance to the circuit, will take the readings from exact infinity down to zero, where an electric current will flow through the circuit. The resistance gives an unlimited value if the test component separates from the electrical circuit. And the needle reaches for infinity. If a large amount of current moves the meter exhibits null resistance.

On the other hand, with zero current the meter will exhibit a significantly higher resistance value. Whenever the test component is attached to the circuit in series, the resistance of the circuits. And the needle will move towards the left. Also, the needle will move in the right direction with little resistance.

Shunt type ohm-meter:

Ohmmeters of this type must be connected parallel to the battery and display resistance by rolling the needle in the left direction. Testing of infinity spots and current is not possible with a shunt-type ohm-meter. There is also an additional consideration that the electrical meter automatically exhibits zero amperes of current if the resistance
shows zero. Furthermore, the current will move from the battery, causing the needle to point in a leftward direction with the rise in resistance value.

Multi-range Type Ohmmeter:

There is a wide range of resistance values available with this kind of ohm meter. Also, an adjustable range is available, so according to the condition, you can select the appropriate range. The key thing to keep in mind is that the measuring element is located parallel to the meter in this type of ohmmeter. Furthermore, the deflection of the needle can also serve to examine the magnitude of resistance.

Types of multi-meter:

The multimeters are available in a variety of models and types. Analog and digital multimeters are the two main categories of multimeters. While an analog multimeter displays many scales with varying values, a digital meter reveals the real value, which is simpler to read and comprehend. More information about the types of multimeters is provided below.

Analog multimeter:

As its name suggests, an analog multimeter uses a moving pointer and a scale to exhibit the results.
A multimeter of analog type is built around a microammeter and features a needle that drifts across a graduated scale. Scale readings are indicated by needle points. These meters are a bit difficult to understand.

Furthermore, these multimeters needed extreme caution because if they dropped accidentally they could be broken. Analog-type multimeters are typically less expensive in comparison to digital multimeters. Analog multimeters also have lower accuracy than digital automotive multimeters.

The needle moves across the scale, so they are excellent for assessing small changes in voltage. In addition, analog testers are highly dependable and have a high degree of sensitivity (scaling down to 50 microamperes) if used as ammeters.

Digital multimeters:

A digital multimeter (DMM) is an instrument of choice for professionals including electricians, technicians, etc. Like analog multimeters, they don’t have any moving parts (scale, needle), rather they contain a digital display or LCD to exhibit results. A variety of digital meters are available nowadays from quite simple to advanced or expensive ones.

Key points:

  • Digital multimeters are designed in a way that it becomes convenient for everyone to utilize them.
  • They display a more accurate reading with minimal chances of errors.
  • Due to high resistance, they have better voltage-meter activity in comparison with analog meters.
  • Some of the higher-end models have an automatic range setting feature.

Wrapping points:

Now, we can conclude that a digital multimeter proves itself a multi-tasker by performing a variety of services like voltage testing, amperes, capacitance, frequency determination, and so on. But if you are only concerned with resistance examination regardless of accuracy, an ohm-meter is what suits you better. Here, analog multimeters and ohm-meters would be suitable choices if one is looking for the cheaper option.

Leave a Reply

Your email address will not be published.