Tool in Focus: The Multimeter

A multimeter is a standard diagnostic tool for technicians in the electrical biz. Here’s what you need to know.

When it comes to detecting faults, the multimeter’s a crucial piece of kit. And it’s tried and tested too – in fact, its origins stretch back an incredible 200 years in the form of the galvanometer. Now, this wasn’t a piece of equipment you could handily carry in your pocket — the galvanometer was a big but delicate device which rendered it pretty useless in the field. Which is just as well, as there wasn’t a great deal of call for it outside of a lab, anyway. 

Multimeters through the ages

Technology progressed and fast forward 100 years and multimeters as we now know them were gaining in popularity as ownership of radio receivers and vacuum tube electronics increased. 

The first true multimeter, known as the Avometer, was invented by an English chap — a Post Office engineer by the name of Donald Macadie — who got the hump with carting about various pieces of equipment to maintain the telecommunication circuits, so created something he could use easily. 

The Automatic Coil Winder Electrical Equipment Company was founded in 1923 specifically to put the Avometer into mainstream production, and while Donald continued his job at the Post Office, his son Hugh joined the business and became technical director. The Automatic Coil Winder Electrical Equipment Company, after a series of buy-outs and mergers eventually became part of Thorn EMI, a well-known UK consumer electronics, security and music company, which also bought Richard Branson’s Virgin Records in the early 90s. True fact.

The modern multimeter

Today’s digital multimeter is a test tool used to measure two or more electrical values—principally voltage (volts), current (amps) and resistance (ohms). It is a standard diagnostic tool for technicians in the electrical/electronic industries.

Digital multimeters long ago replaced needle-based analog meters due to their ability to measure with greater accuracy, reliability and increased impedance. Digital multimeters combine the testing capabilities of single-task meters—the voltmeter (for measuring volts), ammeter (amps) and ohmmeter (ohms). Often, they include additional specialised features or advanced options. Technicians with specific needs, therefore, can seek out a model targeted to meet their needs.

Let’s look at some other popular multis.

Multi… bet

A ‘Multiple’ bet is a bet that consists of more than one thing (let’s say horse for simplicity), with all required to win or place.

Gamblers can place small but ambitious wagers for very high rewards. Bookmakers love multi bets. They make so much money out of them that they may even allow you to get one wrong and get a refund! Remember though, they’re not just being kind.

Multi… lingual

OK, there’s being handy with your languages and just plain old showing off. And this guy’s a show off. Ziad Fazah, who was born in Liberia and now lives in Brazil, can speak (and read and understand) an incredible 59 languages… making him the most multilingual person alive today. We’re sure they all come in very handy on a daily basis… 

Multi… vitamin

Multivitamin pills may be a staple for many of us today, but 100 years ago people had to rely on a good old balanced diet. That was, however, until Carl Rehnbord returned to the US after spending a few years in China, where he had the impact vitamins, minerals and nutrients could have. And so it began. 

Multi… storey

You can’t beat a good multi-storey car park, can you? As long as the clearance height is decent, anyway. And we’ve got a few good multi-stories here in Oz. But to quote Crocodile Dundee, ‘that’s not a multi-storey, this is a multi-storey…’ The West Edmonton Mall in Canada has space for an incredible 20,000 vehicles, and holds the Guinness World Record for the planet’s largest parking lot.