Testing meters such as clamp meters and multimeters are valuable tools to electricians and engineers. While clamp meters offer convenience in measuring high current (amperage), multimeters bring accuracy and versatility, measuring voltage, resistance, low current, and more.
Besides their appearance, both electronic testing devices have many unique differences. However, some individuals have difficulty choosing or distinguishing between both devices, probably because they both test electricity.
This article aims to bring clarity by discussing the differences between clamp meters and multimeters and other related information.
What Is A Clamp Meter?
A clamp meter is an electronic tool that can test and measure parameters (e.g., current) in electrical and electronic engineering. As the name suggests, it has two prominent jaws serving as sensors and features a numeric display.
Also known as a tong tester, a clamp meter can operate optimally without the need for breaking connections or disconnecting the electricity source. It can test whatever parameter is required once powered and clamped at any point around a conductor (e.g., wire).
Basic clamp meters cannot measure multiple parameters except amperage. Modern high-end options can test or measure voltage, current, and resistance in recent times.
What Is A Multimeter?
A multimeter is a more standard test tool for measuring multiple electrical values. It is multipurpose and compact. Generally, it features a central device that houses the display and two colored probes (red and black).
Multimeters require a direct connection to the circuit using its probes. It can measure electric current, voltage, and resistance by changing its settings with its knob.
Advanced multimeters can test or measure continuity, frequency, decibels, conductance, inductance, light level, pH, and even temperature. There are two popular multimeter types – analog (with a moving pointer) and digital (numeric display).
Differences Between Clamp Meter And Multimeter
Even though clamp meters and multimeters are both electrical test tools, some key differences exist. This section compares a clamp meter and multimeter based on five substantial factors.
There are noticeable differences between a clamp meter and a multimeter. Their appearances are generally distinct, and the sizes are relatively different. So, what exactly are the differences in the design?
The most noticeable difference between a clamp meter and a multimeter is the two jaws on the former. A typical clamp meter has two jaws hinged to the primary device in a streamlined fashion.
These jaws (clamp) serve as the primary sensors, opening and closing with the jaw release control on the clamp meter. It is entirely different for a multimeter. The clamp is absent, but a pair of wire probes perform a similar function.
In most cases, a multimeter comes with three input ports to connect the probes, but some models may feature an extra port for additional features. Both wire probes are colored (black and red) and are detachable hence easy to replace.
Clamp meters and multimeters also differ in size. Multimeters are wider, bulkier, and more rectangular, perhaps due to their multiple functionalities. On average, multimeters feature more control buttons, but they come with a rotary switch.
Due to design, a clamp meter is quick, safe, and convenient for any user, including those with basic knowledge of electrical engineering. It is smaller than a multimeter; therefore, users find it easier to handle it with one hand.
Unlike clamp meters, multimeters can either be the more popular digital type or the obsolete analog option. The analog multimeters come with a moving needle pointer and a scale to indicate the measurements.
It is also vital to note that some newer models have detachable clamps or displays for remote or tight tasks. Furthermore, some advanced clamp meters may feature input jacks for wired probes to add more functionality.
Both devices have different modes of operation, and this factor determines their functionality. A clamp meter works based on the magnetic field existing when current moves through a conductor. Therefore, no direct contact with the circuit is necessary.
Both jaws serve as a sensor to measure current (and other values). Hence, there is no need to modify the circuit. The invisible magnetic field around the conductor induces the sensors to produce a reading.
On the other hand, a multimeter needs to connect to the electric circuit (in a series arrangement) before picking a reading. Installing its probes the right way is essential to get the correct values. Someone with little knowledge of electric circuits may be unable to set it up.
For this reason, a clamp meter can measure amperage more conveniently than multimeters. Multimeters can only measure low currents (e.g., ten amps) without breaking a fuse or damaging the meter.
Consequently, clamp meters are the best for measuring current (amperage) with low or high amperage ratings reaching 1000 Amperes or more. However, some can test for voltage and resistance with lower accuracy.
As mentioned earlier, multimeters are multipurpose and can do more functions than most clamp meters. They can measure or test for the following electrical parameters:
- AC and DC amperage.
- AC and DC voltages.
- Capacitance, continuity, and inductance.
- Temperature (in advanced models).
Resolution and Accuracy
The resolution or display counts refer to the lowest part of the readings a meter can display. It refers to the maximum number that can appear on a meter. Also, it is the total number of digits a meter’s screen can display.
Multimeters can measure in milliunits (e.g., milliamps), but clamp meters offer a lower resolution, measuring to the nearest hundredth or tenth. A multimeter provides a higher degree of accuracy than a clamp meter. It is primarily a result of the non-contact working design of the latter.
Digital multimeters have an accuracy of about 0.5%, while their analog counterparts are around 3%. Conversely, clamp meters have a fair accuracy of 2% when measuring for AC or DC. Notwithstanding, clamp meters are still acceptable for general use.
Clamp meters are incredibly safer to use than multimeters since there is no actual contact with electric currents. The clamp goes around the wire (even with insulation), and the device produces a reading.
Connecting a multimeter is complicated because it requires direct contact with the wiring (in a series arrangement). Not everyone is familiar with setting up an electric circuit. Hence, the chances of becoming electrocuted are higher.
When using a multimeter, be careful when handling wires and circuits. Switch all power sources before connecting a multimeter. Wearing electrical insulation gloves can protect users from high voltage power supply.
Most multimeters and clamp meters are within a similar price range. In general, multimeters may cost slightly more due to their higher accuracy, versatility, and resolution. Furthermore, high-end multimeters that offer several features are more expensive.
Clamp Meter vs. Multimeter: Which One You Should Buy?
Considering the differences between a clamp meter and a multimeter, finding the proper tool for the right task is crucial. Here are some guidelines for choosing between both meters.
Basic digital multimeters – are ideal for measuring voltage and testing for continuity. They are easy to use for less experienced operators. An example is the INNOVA 3320 auto-ranging digital multimeter.
High-end digital multimeters – are suitable for experts for power tasks. They are ideal for tasks that require high accuracy. Also, they work excellently for jobs requiring advanced functionalities, e.g., battery, transistor, diode, and continuity tests. The Fluke 87-V digital multimeter is an excellent option.
Basic clamp meters – are best for measuring currents quickly and safely. They do not require a high level of expertise. E.g., the Extech MA445.
High-end clamp meters – are perfect for measuring amperage, resistance, and voltage of potentially high-power circuits. They are suitable for correcting irregular breaker trips. The Fieldpiece SC440 True RMS clamp meter is an appropriate option.
Read more: Best Multimeters For Automotive 2022
1. Is an ohmmeter the same as a multimeter?
No. A multimeter can indeed perform the function of an ohmmeter, measuring electrical resistance. However, it is not the same as an ohmmeter as it offers more functionality. A multimeter can measure voltage and current, which an ohmmeter cannot do.
2. Can I use a clamp meter to measure voltage?
Yes. Since a clamp meter functions primarily on electromagnetism, it can measure voltage. Depending on the model, it can measure the voltage in alternating and direct current circuits.
Picking a clamp meter or a multimeter depends on the task and the operator’s experience level. A basic clamp meter is enough to measure current with minimal effort. Multimeters are preferable to measure resistance or voltage.
A clamp meter is the best choice available to avoid breaking a circuit. Concerning safety, clamp meters are safer. On the other hand, multimeters guarantee a higher accuracy and resolution expected by a technician or engineer.