Today I feel inclined to talk in this brief post about the one tool that I don’t think anyone who is living off the grid should be without. The tool that I’m talking about is a digital multimeter. If you’re not familiar with this tool, let me take just a minute and tell you about it. A multimeter is a tool that is used to measure various aspects of electricity.
Let me give you a good example. I’m currently experimenting with different permanent magnet motors to see how much voltage they put out when I spin the shaft. I’m trying to pick a motor to use for my next project. Without a multimeter, there wouldn’t be any way of knowing how much voltage each motor produces at a particular RPM. Sure, some people might try and just attach a light bulb to the wires coming from the motors that they are testing and see if the motor lights the bulb when the shaft is spun but that won’t really tell you much.
It will tell you that voltage is in fact being produced by the motor but that’s all you’ll know. You’ll have no idea how much voltage is being produced or how many amps are flowing through the wires. With a multimeter, you can learn all kinds of things. For example, you might learn that a certain voltage is produced when a motor is spun at a certain speed. Knowing this will help you know if a particular motor would be a good candidate for use in a homemade wind turbine.
The multimeter that I have now cost me about $50 but for years I used a $20 model and it served me quite well. I can’t stress how useful this little gadget will be to you. If you don’t own one, the next time you are in town I highly suggest that you pick one up and start learning how to use it. Trust me when I say that you be glad you did!