Quick Overview
Handheld Multimeters are ideal for portability and general use, while Benchtop models excel in accuracy, measurement speed and advanced functionality for professional and laboratory settings.
Introduction
What is a Digital Multimeter or DMM?
It is a tool. And not just a tool. It’s the most important tool in the electrical / electronic engineer’s or technician’s toolbox.
A digital multimeter is used to measure electrical values such as voltage (AC / DC), current (AC / DC) and resistance. The simplest of multimeters can be used for testing household wiring, batteries and power supplies. Modern digital multimeters can also be used for continuity testing, measuring capacitance, inductance, frequency, duty cycle, temperature and for diode testing.
Digital multimeters are available as handheld devices and as benchtops with a front panel display.
Handheld DMMs are portable devices that support the measuring and testing functions listed above.
Benchtops digital multimeters support all of the measurement functions that are available on handheld multimeters. In addition, benchtop multimeters have higher accuracy, higher resolutions and faster reading speeds compared to handheld multimeters.
Summary Table
The following table summarizes some of the differences between handheld and digital multimeters. The values listed are representative and should not be taken as absolute limits.
Table 1: Handheld vs Benchtop digital multimeters.
| Specification | Handheld Multimeter | Benchtop Multimeter |
|---|---|---|
| Resolution | 3.5 to 4.5 digits | 5.5 to 8.5 digits |
| Reading speed | Up to 40 readings per second | Up to 100,000 readings per second |
| Accuracy | 250 to 5000 ppm | 8 to 250 ppm |
| Range | Higher voltage ranges | High voltage range |
| PC connection | Very few support this feature | Supported |
| Portability | Highly portable | Not portable |
Handheld multimeters are portable and rugged devices which can be used in harsh working conditions. They are used for household / industrial electrical troubleshooting, academics and DIY electronic projects. Some high-end handheld units can be used for special applications such as measuring the resistances at welding seams and measuring low-resistance at outer skins for aircraft.
Handheld DMMs comply with power safety and regulatory standards and some are IP 67 certified. Handheld DMMs are used for measuring high voltage sources and usually have a higher-rated measurement category compare to benchtop DMMs. Some handheld units come with features that are useful in harsh environments such as a flashlight, OLED display for better viewing in dark locations and contactless voltage sensing for helping to locate live wires.
Benchtop multimeters are used by test and validation engineers and product designers. They are made using high-performance and high-precision components and circuits that enable higher precision and accuracy that are required for designing and testing applications. Consequently, benchtop multimeters are also more expensive. The four-wire measurement capability that is supported by most benchtops also provides a greater level of accuracy.
Test and design engineers need to take thousands of measurements for thorough characterization of products. This can only be done by benchtops units.
Benchtop units also support multiple interfaces, such as USB, Ethernet and RS-232, for interfacing with external devices. Most benchtop units also support remote language programming through Standard Command for Programmable Instruments (SCPI) compatibility. This enables use of programming software for automation of test sequences.
Benchtop units come with a larger display that can display charts and histograms.
💡 “A good tool improves the way you work. A great tool improves the way you think”. – Jeff Duntemann
Because of their advanced capabilities, benchtop multimeters provide insight for engineers and technicians which enables them to not only view, but also to understand the behavior of electrical and electronic systems.
PRODUCT COMPARISONS
Lets take a look at a similarly priced handheld and a benchtop unit. The handheld unit is the Fluke – 179, and the benchtop unit is the Siglent Technologies SDM3045X Multimeter. Both cost around the $390 mark. One reason for the handheld Fluke costing so much is that its NIST calibration certificate has a fee which is obviously included in the product price.
Table 2: Comparison between similarly priced handheld and benchtop DMMs
| Specification | Siglent SDM3045X | Fluke 179 |
|---|---|---|
| Counts | 6000 | 6000 |
| Resolution | 4.5 digits | 3.5 digits |
| Max AC voltage | 750 Volts | 1000 Volts |
| Max frequency | 500 kHz | 100 kHz |
| Operating temperature | 0 to 50 ºC | -10 to 50 ºC |
| Weight | 3.6 kg | 420 grams |
| Interface | LAN, USB | NA |
| Programmer language | SCPI | NA |
| Histogram | Yes | NA |
| Trend chart | Yes | NA |
| Memory | 1GB Flash | NA |
Note: the list of specifications for both products is much more extensive. However only those specifications have been chosen for Table 2 that help to highlight the differences between the handheld and benchtop units.
As is evident from the table, the handheld unit is more suitable to field work involving troubleshooting of AC and DC electrical systems.
The benchtop unit has features that allow for detailed analysis and characterization of products that are being developed. The benchtop unit can also be interfaced with a computer for running advanced analysis procedures.
The following is a comparison between the Fluke 8808A benchtop multimeter and the Siglent SDM3065X. The Fluke unit retails for around $900 and the Siglent unit retails for around $750.
Table 3: Fluke 8808A vs Siglent SDM3065X
| Specifications | Fluke 8808A | Siglent SDM3065X |
|---|---|---|
| Resolution | 5.5 digits | 6.5 digits |
| Interfaces | RS-232, USB | USB, LAN |
| Programming languages | ASCII, fluke remote command emulation | SCPI |
| Dual display | Yes | Yes |
| DC range | 200 mV to 1000 V | 200 mV to 1000 V |
| AC range | 200 mV to 750 V | 200 mV to 750 V |
The table shows that the Fluke 8808A and Siglent SDM3065X are pretty close in terms of specifications. However, there are some features on the Fluke unit that make it stand out.
There are six setup buttons on the unit which can be used to setup common measurements. Once the measurement is setup, a single key has to be pressed to make that measurement. This makes complex measurements easy and reduces that possibility of errors. Furthermore, the display on the unit comes with enunciators which clearly display whether a test has passed or failed.
Other than that, Fluke is a name which is renowned in test and measurement. And that is something that we should not ignore. Fluke has built up its reputation over many years. And that is not something that happens by chance. Obviously they build top-notch products which are reliable and perform well. And if their products cost a bit more, then that is to be expected.
Now lets look at another comparison between two moderately priced products which both cost around the $450 mark: these are the Rigol DM3058E and the Siglent SDM3055.
Table 4: Rigol DM3058E vs Siglent SDM3055
| Specifications | Rigol DM3058E | Siglent SDM3055 |
|---|---|---|
| Resolution | 5.5 digits | 5.5 digits |
| Dual display | Yes | Yes |
| Display | 256 x 64 LCD | 480 x 272 LCD |
| Interfaces | USB, RS-232 | USB, LAN |
| Measurement speed | Max 123 reading per second | Max 150 readings per second |
| DC voltage | 200 mV to 1000 V | 200 mV to 1000 V |
| DC current | 200 uA to 10 A | 200 uA to 10 A |
| AC voltage | 200 mV to 750 V | 200 mV to 750 V |
| AC current | 200 mA to 10 A | 20 mA to 10 A |
| Programming language | SCPI | SCPI |
As is evident from the table, the specifications and features of both benchtops are quite similar. However the Siglent SDM3055 seems to have the edge over the Rigol DM3058E because of larger display size and resolution, higher measurement speed and the Ethernet interface.
SUMMARY
Many tools are available in the market for electrical and electronics engineers. One of the most important of these tools is the digital multimeter or DMM. Specialized DMMs have been developed for different applications. In this article, we have covered the major differences between handheld and benchtop DMMs and their applications. We have also performed the following product comparisons
- Comparison between similarly priced handheld and benchtop DMMs (Fluke 179 vs Siglent SDM3045X)
- Comparison between two high-end benchtop DMMs (Fluke 8808A vs Siglent SDM3065X)
- Comparison between two moderately priced benchtop DMMs (Rigol DM3058E vs Siglent SDM3055)
