USB Chargers | Electrical Safety First
There was a time when every device seemed to come with its own unique charger. Remembering to pack the right charging cable was a must if you wanted to continue using your device whilst away from home. However, the Micro USB has combatted the industry’s use of custom ports and now charging your phone on-the-go is no longer a problem with the standardised connector.
There are many different important elements you should be aware of when it comes to USBs. We’ve covered all you need to know about USBs and answered some of the most frequently asked questions. In this article we will cover:
How USB charging works
When it comes to USB networks there is always one host and one device. The majority of the time the computer is the host and your appliance is the device. Power flows from the host to the device however data can flow freely between. A USB cable has four wires and a USB socket has four pins. The outside pins provide a 5 volt power supply in combination with the inside pins which carries the data.
Types of USB
The types of USB refers to the physical shape of the plug.
The classic USB plug that we are all familiar with, the Type-A USB is the larger standard rectangular plug. Whilst it’s gone through a number of changes to accommodate different versions of USB, the design of the plug remains the same, which means that all Type-A plugs and sockets are compatible no matter what version they are.
Usually the other end of a USB cable uses a Type-B connector. The Type-B plug is the tall plug with the slanted top corners. Variations on Type-B have been widely adopted due to the sheer necessity of having smaller plugs at the client device end.
The mini USB and micro USB are also variations of Type-B.
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USB Micro-A
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USB Micro-B
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USB-C
The headline feature of the USB-C is that it's reversible. It’s designed to be small enough to not need any mini or micro variants. The intention is that it will completely replace all types of USB on both host and client devices.
USB charger versions
The various upgrades focus on improvements in terms of speed and features. Since its official release in 1996, there have been five versions of the USB:
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USB 1.0
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USB 2.0
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USB 3.0
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USB 3.1
Whilst the USB 3.0 is currently the most common, it is predicted that the new USB-C connector could eventually replace this. The USB-C (or the USB Type C) was made widely available from 2015, and is now common on new model smartphones as well as some laptops. The intention is that it will completely replace all types of USB as the USB-C is a replacement for both ends of the cable. USB-C 1.0 brings in the new power standards and speed advantages similar to that of USB 3.1.
How USB-C charging works
The USB-C is entirely different from its predecessors. The connector is universal and therefore it will work when used either way. It also outputs more power, as well as the theoretical output. There are also plenty of USB chargers that don’t fit into this specification, such as AC adapters.
Types of USB port
There are three types of USB port dictated by the actual current specs (milliamps or mA).
Dedicated charging port
A dedicated charging port applies to power sources like wall chargers that do not enumerate, so charging occurs with no digital communication at all.
Downstream port
A charging downstream port can be found on a computer or laptop and can supply up to 1.5A, whilst allowing a USB to be detected and begin charging before enumeration (which is when the digital communication takes place).
Standard downstream port
A standard downstream port can be found on a computer or laptop and needs to enumerate (start digital communication) to be USB compliant, however most present-day hardware does draw power without enumerating.
Voltage and Amperage
Not all USB connectors, cables and chargers are equal. For example, some wall chargers can supply more power than others and one particular USB socket on a laptop may vary in power from the others, or PCs with some able to charge whilst in sleep mode.
You will also need to consider Amperage. Chargers increase the current to provide a higher amount of power quickly – this is measured in amps and the more amps means the more power. Therefore, a charger that comes with a smartphone will provide less amps than a charger that come with a tablet. You will need to consider voltage and the equipment you’ll need to use to enable the use of USB chargers when travelling internationally.
Safety Concerns
Uncertified chargers come with serious safety concerns. Similar to unofficial batteries, uncertified chargers can be bought at a reduced price online, from overseas or in high street shops and these kind of electrical products may present a higher risk of exploding or catching fire. Not only do they present a risk to you, the use of uncertified chargers may also damage your phone (which in turn could void your guarantee).
Cheap devices often fail to meet the requirements of the Electrical Equipment Regulations Act 1994. The money that you save comes with extremely high risks and therefore buying a branded/certified charger is essential to avoid often fatal repercussions.