I would like to take a moment to discuss frequency. In electrical, frequency is defined as the number of cycles per second that an alternating current will change direction (measured as a Hertz, the symbol used is HZ, and is named after German physicist Heinrich Hertz, the first to broadcast and receive radio waves). It is an international unit of measure where 1 hertz is equal to 1 cycle per second. In Canada, our electrical power is set to run at 60 HZ per second, and thus, all the things we plug in and use are set to run at 60 HZ too. Just imagine the electrons darting back and forth on the copper conductor 60 times per second, ultimately trying to find ground, and the only thing stopping it is the insulator covering that conductor.
Some countries run at 50 HZ. There’s a full list of the frequencies each country uses as well as the standard voltages. Table of Voltages and Frequencies from Around the World Ever wonder why some countries you have visited require an adapter for your plug in stuff? Well that’s why.
There are actually many common frequency ranges in electricity, used for a variety of applications. The equipment and circuits can be designed to operate at fixed or variable frequency, which means sometimes it okay for the frequency to change but sometimes not. For instance some electrical motors can either slow down or speed up with the frequency change, and this is by design. Here are some frequency variety examples:
- Power line frequency (normally 50 Hz or 60 Hz). This is what comes out your plugs in your houses.
- Variable-frequency drives, which normally use a 1-20 kilohertz (kHz) carrier frequency. used in electro-mechanical drive systems to control AC motor speed and torque by varying motor input frequency and voltage.
- Audio frequency: 15 Hz to 20 kHz (the range of human hearing).
- Radio frequency: 30-300 kHz. suitable for use in telecommunications. Radio waves travel at one cycle per second (1 Hz). (Similarly, a clock ticks at 1 Hz.)
- Low frequency: 300 kHz to 3 megahertz (MHz). also radio. Doesnt travel far though.
- Medium frequency: 3-30 MHz. AM radio.
- High frequency: 30-300 MHz. shortwave radio.
The word frequency can also be described as the rate at which something occurs or is repeated over a particular period of time or in a given sample. The frequency in which one practices an action, will find the practicing individual an inevitable improvement of that action. This is true of what we think, do, how we play, even how we love. How we build our strengths and our weaknesses. The frequency of what we choose to practice determines what we become good at, to our detriment or to our benefit. What I’m trying to say is, if you want to be good at something you will need to practice. I think we can agree that people get good through repetition. And no matter what you choose to do, if you do it frequently it will shape who you are.
That is why when we go to work at something everyday, we get good at it and start to call it a career. If we do things we do not want to be good at, like watch tv, we might regret pouring so much time into watching tv. To become a better ukulele player, you will have to practice your ukulele. To become a better electrician, you will have to practice being an electrician. Keep up with your code changes, and go over the forgotten or little used knowledge from school. Try to learn new things at work as the field of electrical is vaste and will never cease to have new things for you to master. Each day could be considered a cycle, where we practice waking, eating, surviving, thriving, sleeping. Each of us mere electrons seeking ground, a tiny zing in the big scheme of the universe.