We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is a Positive Terminal?

By Paul Scott
Updated May 17, 2024
Our promise to you
AboutMechanics is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At AboutMechanics, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

The term positive terminal describes which of the two connection terminals on direct current (DC) equipment supplies or is meant to receive a positive electrical charge. DC power supplies always feature a positive to negative electron flow and always have a negative and positive terminal. Most DC appliances or machines also have a positive and negative terminal which should always be connected to terminals of same orientation on the power supply. Failure to do so can cause severe damage to the equipment and power supply. This positive/negative relationship is commonly known as the polarity of a supply or device.

Any source of direct current electrical power flows from a positive source to a negative source. This applies to the DC side of rectified alternating current (AC) power supplies, batteries, and solar panel outputs. Each of these DC power sources feature a positive terminal and a negative terminal. The permanent relationship between positive and negative sides of DC power supplies is referred to as the polarity of the supply. Power supplies and appliances typically include a ground or earthing connection as well; this has nothing to do with the supply of power or the polarity of the device, however.

The universal color code and symbol for a positive terminal is red and a plus (+) sign. The color code and symbol for a negative terminal is black and a minus (-) sign. The polarity relationship, color codes, and symbols for positive and negative terminals are also used on the devices powered by DC power supplies. The connection terminals on DC power supplies and devices will always be marked with one or both of these identifiers. When connecting DC devices to a power supply, it is crucial to observe the correct polarity. In other words, the positive terminals on the supply and device should be connected to each other with the same applying to the negative terminals.

In some cases, reversal of polarity can be used to change the direction of operation for some devices and may be included in the controls as a design feature. Some types of resistive DC appliances such as heaters lack specific polarity requirements and will have no markings on their terminals. Generally, DC devices are polarity specific; failure to observe correct polarity will result in damage to the device and the power supply. This applies to all polarity dependent DC appliances devices including loud speakers, motors, capacitors, and electronic equipment.

AboutMechanics is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Discussion Comments

By SarahSon — On Jul 20, 2011

It seems like I am always putting in the wrong side of the battery when I am replacing batteries in something. One time I stuck four rechargeable batteries into a battery pack and plugged it into the wall.

I didn't pay any attention to the light or even realize that they didn't go in very easy. The next day when I went to get the batteries, I was frustrated that none of them were working.

It was not until then that I realized I had put the positive battery side in the wrong way on every one of them.

By myharley — On Jul 20, 2011

You will know right away if you don't have the right cable connected to the proper terminal. This was a learning experience for my daughter when her car would not start.

She carried a set of jumper cables with her in the trunk of the car, but somehow the dome light was left on in her car and it would not start the next morning.

She was trying to take of this by herself, but she hooked up the wrong end of the cable to the car battery positive terminal. Obviously nothing happened, and she didn't know what else to do so called someone for help.

She was pretty embarrassed when she realized what she had done, but will never let that happen to her again.

AboutMechanics, in your inbox

Our latest articles, guides, and more, delivered daily.

AboutMechanics, in your inbox

Our latest articles, guides, and more, delivered daily.