How do I use a multimeter?

With so many functions on a modern or advanced multimeter, and so many reasons why you may want to use one, it would be impossible to answer the question 'How do I use a multimeter?' comprehensively. However, most modellers will only want to check one of two things, and probably with a fairly basic device, so here are a few tips that might just help.

If you want to measure how many volts are going through a circuit, select the 'volts' option on your multimeter. If your meter has several volt values to choose from, select the next highest value up from the maximum of whatever it is you're testing (for instance if expecting 15V, select 20V or 50V but not 10V). Next, simply touch the two terminals on the ends of the wires coming from your multimeter to the positive and negative wires of your circuit and check the reading on your device. If you have no reading at all, it may be that you have your terminals the wrong way round, so swap them over and try again (this only applies to DC power supplies).

Top Tip: If you still have no reading and think you may be using the meter wrong, use a section of live track that you know to have full power running through it, touch the rails with your terminals and you should get a reading of around 12-14v. This way you will at least know that the meter works and you are using it correctly.

If it is an unpowered circuit you wish to check for any breaks or a short circuit, select the ohms setting on the multi-meter. This setting will have a symbol that looks like a horseshoe. Before you test the circuit, touch the two terminals of your multimeter together and you should get a strong reading. If a reading is displayed, you can repeat the exercise this time touching the terminals to the circuit you wish to test, if you get a reading, your circuit is complete. If you didn't get a reading when testing the meter, check the batteries of the multimeter.