If you’re a budding electrician, a multimeter is a vital piece of equipment for measuring voltage, resistance and current. Online retailers like Rapid sell a variety of multimeters, but there’s no sense picking one up until you know how to use it. This guide cover the basics of measuring voltage and resistance.
Your multimeter should come with two leads: a red one and a black one. These are connected to the component or part of the circuit that you’re measuring, and a digital display reads out the recorded measurement.
To measure voltage, attach the red cable lead to the positive end of the battery or circuit and the black lead to the negative. Next, set the dial in the centre of the multimeter to the level of voltage you expect to receive.
For a device that requires a pack of four batteries, it is expected that you’ll receive a reading of six volts. Over time, performance of batteries deteriorates, so if you receive a measurement that’s lower than you expect, it may be time to upgrade your batteries. Almost all portable electronics use direct current, so make sure that you have your multimeter set in the DC range.
If you never memorised the colour coding that identifies the resistor rating, a multimeter can save you the time of consulting the internet and adding the value of coloured bands together.
Lightly press the two leads to the component ends of the resistor and set the multimeter dial to the resistance you expect to record. If the value on the display reads as ‘1’ or ‘OL’ then the device has overloaded and you set thevalue too low. Simply set the dial to a higher setting and test the component again.
Alternatively, if you get a reading that’s close to zero, you need to set the multimeter to a lower ohms setting.
There are a lot of instructional videos on YouTube that can help you with this process. This one shows you how to use a multimeter to test items around the home.