What to look for when buying USB-C cables and adapters

Buying a cable shouldn't be difficult. It doesn't have to be if you follow these simple tips.

USB standards have a long history, and they've gone through plenty of changes since first implemented in 1996. The premise behind it all is providing a way to standardize cables, connectors, communication, and power transfer between electronic devices. Some of the first equipment to use USB were the really old, brightly colored iMac and speakers. USB was designed to be the one standard that does it all, and that's pretty much how it all worked out.

You can think of USB-C as a set of rules to make smarter USB plugs, cables, and connectors.

The USB-C specification is one of those USB standards. Released in August 2014, it's a set of rules for a small 24-pin reversible plug connector to use with existing USB system. Some of the connections inside are used to tell which way a cable is plugged in; others are used to transfer data or power; and some are used as a dedicated connection to allow both sides to talk to each other, and make sure the right amount of electrical current is being sent to safely charge or power one device from the other. Though it was released in tandem with the USB 3.1 specification, USB Type-C rules are only for the physical connections — data speeds are covered by other rules. You can think of USB-C as a set of rules to make smarter USB plugs, cables, and connectors.

More: Getting to know USB-C infographic

The best parts of the USB-C specification are also the parts that make buying the right cable or adapter important. With USB-C, all connected devices can send power out as well as receive power in. You can charge a phone or set of headphones or anything else that uses the USB-C spec with another phone that uses the USB-C specs. You could (in theory) build a cable that can pull power from several Lumia 950s or Nexus 6Ps and charge the battery in a MacBook if you wanted to.

Buying the right cable is a must or you risk damaging the things you're plugging in, or even starting a fire.

USB-C also includes a native way to "fast-charge" one USB-C certified device from another safely using that dedicated connection channel mentioned above. It's also an open specification that anyone can use and alter to better suit their needs, and companies making phones have done just that. This means buying the right cable is a must or you can risk damaging the things you're plugging in or even starting a fire.

More: This USB-C problem isn't going away anytime soon

But don't fret. You don't need to know all the rules in the USB-C spec or how it can tell which way it's plugged in or any of the other geeky details to make the right choice if you follow a few easy tips when you're buying a cable or connector. These three tips will help you get exactly what you need.

Buy a reputable brand

We've all seen ultra-cheap USB cables online or at the drug store and were tempted to buy them. While still not the best idea in the world, most of the time that was fine with the older USB Type-B micro standard used on most phones and other gadgets. Low voltage and low current were sent on the same pins every time, and the cable only went in one direction. That's changed, even for the older Micro-USB "standards" because of the need for faster charging.

Don't buy a USB-C cable just because it's cheap.

When you're buying a USB-C cable or a connector, look for a well-known brand. This is the best way to make sure the cable is using the appropriate size wires inside, the connector is properly constructed and the right resistance is being used. All three of these things are important when you're sending more current over tiny wires, and cheaply-made cables that aren't using the right components can be dangerous.

Cables and adapters from reputable companies often go on sale and for just a few dollars you'll have something a lot safer than you might get if you buy cheap generic-packaged cables. The best part is that we want to save money on good cables, too, and when we find a great deal we'll share it right on our homepage and on social media.

Know what you need

Remember when we said the USB-C spec was an open standard that companies can change to better suit their needs? Phone manufacturers are doing that, and sometimes the cables and chargers they sell and use aren't compatible with all the rules. Qualcomm's Quick Charge is really popular, and they can use a USB-C connector sometimes that isn't fully compatible with the standards. Other companies have their own proprietary fast charging methods, and they, too, may not be fully compliant.

Not everyone is using USB-C in a standards compliant way, so be mindful of "quick charge" methods.

If your phone has a USB-C port you can look at the papers it came with or online to see if it uses the port in a non-compliant way. Terms like "Quick Charge" or "Turbo Charge" or any other trademarked fast charging method are a dead giveaway. The list of devices doing this is always changing but at the time of this writing phones from OnePlus, HTC, LG, and Samsung that have a USB-C connector aren't fully compliant, and you shouldn't use the charger, cable, or any adapter that came with them for any other piece of equipment that has a USB-C port. A third-party high-quality cable that follows the specifications can be safely used for these phones, just don't go the other way and order extra cables from one of these companies to use with other equipment.

Your best bet here is to use the charger, cable, and any adapters that came with the phone itself. When you need a replacement, check the manufacturer's website or hit them on Facebook or Twitter to find out which cable they recommend.

So far, phones, tablets, and laptops from Google, Apple, and Microsoft have all been fully USB-C compliant. A quality third-party cable or adapter that's built correctly (that's what these three things tell you) will work fine for any of these devices. Just don't use something from HTC or OnePlus or any other company that may be using the connector differently.

Meet Benson Leung

Benson Leung is a software engineer at Google. He's also the best friend we could ask for when it comes to buying quality USB-C compliant cables and adapters because he tests them in his spare time. Thanks, Benson.

This is important because there are a lot of cables that have a USB-C plug on one end and a "regular" USB plug on the other that are non-compliant in a dangerous way. Besides using the appropriately sized wire and properly shielding the cable and connector ends, a "regular" USB to USB-C cable requires a 56k Ohm resistor to act as what's called a "pullup" on the VBUS (pins 2 and 17 if you're curious) power channel. This is one of the things you need so a USB-C device can let a power source know how much current to send and when to stop sending it. Using a cable with the wrong size wire will damage the wire. Using a cable with the wrong size resistor can damage the things plugged into each end, which costs a lot of money and could possibly start a fire.

You can test the resistance of a cable yourself, or you can see what Benson says. Thanks, Benson!

This isn't just a problem with bargain-bin cables, either. Some very high-profile companies have had (or still have) issues with their cables. If you're the type who has fun doing things like testing continuity and resistance of USB cables, that's awesome and you should test everything you buy then share your results. If you're not, you can check to see if a cable is "Benson Leung approved."

Thanks to the magic of Amazon, this is easy. Leung makes a habit of leaving feedback for all the cables he tests at Amazon. You can check to see if he's in the comments and reviews section and if so, see if he says the cable or adapter is safe to use. This is a no-brainer. Before you buy a USB-C cable, check to see if it passes the test. We'll make it easy — just check out the list below.

See at Amazon

USB-C isn't dangerous. It's capable of safely delivering relatively high current as long as the proper equipment is used, and offers a lot of benefits because of the way it can communicate with other compliant devices. What started out by powering small speakers in the late twentieth century is now robust enough to talk with the instruments used to make music and the bus the band drives to concerts. It's important to use the proper cables and adapters, though.

Just follow these tips and you'll be fine.

Source: What to look for when buying USB-C cables and adapters