Why voltage matters
by Michael Choe | July 19, 2022
Before the pandemic, I used to travel often. One item I always made sure to bring with me when traveling to another country was a plug or outlet adapter. I remember my first trip to South Korea when I stressed out because none of my devices could plug into the outlets. Then there was my first time to Japan when my U.S. plugs fit into the outlets, but they seemed to work significantly slower.
Voltage is the force that makes electricity flow. The common household in the U.S. uses two 120v lines throughout the home. Most U.S. devices will be rated 120v and be sufficiently powered from one line. Bigger appliances (such as a large air conditioner, oven, or refrigerator) will require 240v which means it will use power from both 120v lines simultaneously.
Typically, there are only a few places in a U.S. household where both 120v lines travel through, like the kitchen. If you tried to plug in a 240v appliance in one of your bedroom outlets, you might run into problems. If you have access to your breaker, you can see which rooms’ outlets can only provide 120v and which can provide both 120v and 240v.
It’s important to know the voltage that devices require and the voltage outlets provide. If there is too little voltage, the devices won’t operate at their fullest potential. In Japan, it took noticeably longer to fully charge my phone without a voltage converter because the charger was rated 120v but Japan’s outlets only pushed 100v.
On the other hand, if there is too much voltage, that could severely damage a device. When I was in Korea and used a hair dryer I brought from home with an outlet adapter, I noticed a burning smell getting stronger each time I used it. When I took a closer look, I noticed a small part on the back of the hair dryer melted a bit. This was because of the difference in voltage — outlets in Korea supplied 220v, which was too much for the hair dryer that only needed 120v. That’s when I also learned that not all outlet adapters also function as a voltage adapter.
Because of these experiences, I always check the voltage when looking into new appliances and make sure I have an outlet that can properly supply the device. Also, researching voltage is now an item on my checklist when planning to travel to a foreign country. That way, I know my devices will stay in good working condition at home and abroad.
Michael Choe is a digital communications and social media specialist at Hawaiian Electric Company.
