Guide to USB power sockets

USB ports are increasingly becoming the most convenient means of charging electronic devices at work or at home. The past few years have seen a move away from charging leads that feature dedicated three-pin plugs (in the UK) to leads with a USB connection attached.

The reason for this change is one of convenience: it allows people to charge their devices from most places with a USB port, including a PC, laptop or USB plug. Three-pin plugs are also bulky to transport and store.

The next natural step has been to produce power modules (plug sockets) featuring USB ports, either on their own or in combination with standard three-pin power ports.

These ports can be used to charge a range of devices, such as

  • Smartphones
  • Tablets
  • Kindles
  • Headphones
  • Bluetooth speakers
  • Fitness trackers
  • Portable power packs
  • MP3 players
  • Smart watches

USB chargers for communal areas

One of the most popular uses for USB plug sockets is as a communal charger within areas such as:

  • airports
  • conference tables
  • office hot-desking facilities

USB sockets found in these locations are often positioned centrally on a table or bench, rather than at the bottom of a wall near the floor as with traditional plug sockets.

Placement of USB power sockets

You can choose to position your USB socket almost flush with the surface on which it is placed (in desk) or standing on top of it (on desk). Below is a selection of the USB ports on offer at CMD for either position:

On desk

Image Description Product

One USB Type A socket (maximum 2.4A) and one USB Type C socket. When plugged into a compatible charger, the smartphone can take advantage of a higher voltage (12V or 9V rather than 5V) and draw on a stronger current as a result. (Note: This only applies to chargers with USB-C sockets.)

Sure Charge USB Type A and C Charger

4A USB charger, guaranteeing 2A per socket. Thermal cut-out and short-circuit protection.

Chip On Desk 4A Twin Port USB Charger

Choice of international power, data and media connectors. UK sockets are individually fused at 3.15A or 5A to allow compliance with BS 6396.

Contour Power USB Charging, Data & Media

Choice of international power, data and media connectors. Fully segregated power and data.

Harmony Power, USB Charging, Data & Media

Four plug sockets available, allowing various configurations of plugs, USB charging, RJ45 and HDMI.

Inca Power, USB Charging & Data

In desk

Image Description Product

4A USB charger (shared between two sockets). Supports a range of international sockets. Designed to deflect spillages.

Porthole IV Power & 4A USB Charger

Choice of international power, data and media connectors. Smooth-action lid that retracts to allow easy access from both sides. Shadow gap allows lid to be closed while sockets are in use.

Reveal Power, USB Charging, Data and Media

Configurable to include- power, data and media sockets. Available in four cut-out sizes for desk mounting (69mm x 163mm (A); 69mm x 263mm (B); 69mm x 363mm (C); 69mm x 463mm (D)).

Surface Power, USB Charging, Data & Media

Available as portrait or landscape. Suitable for mounting in soft seating/working walls.

Face Power & USB Charging

What to look out for

One thing to take into account when choosing a USB plug socket is the strength of the electrical current it offers (measured in amps). Devices with larger batteries will require higher amps to charge at a reasonable speed. For example, most smartphones need 1A to charge reasonably quickly, while a tablet (containing a larger battery) usually needs around 2A. This means if you try to charge a tablet from a port that only supplies 1A, it is likely to take some time.

The following table shows the current available from different types of charging equipment:

Device Current

USB port in a PC


Smartphone charger




USB plug sockets

Up to 4A

Some USB plug sockets that contain multiple ports will split the power between devices when two or more are charging. This means two tablets charging from a USB plug that shares 2A between them will each receive 1A of current. This may affect charging times.

How do USB chargers work?

USB involves:

  • a host—the hardware out of which the power flows
  • a device—the electronic device drawing power from the host

In some cases, the host will be a PC or laptop, which can be inefficient. If the host is a mains socket, you will be able to charge at a better rate.

During the transfer of data, information can flow between the host and device, and vice versa.

A USB cable is made up of four wires, while the socket features four pins. The inside pins carry data while the outer pins and the inner pins supply 5V of power.

For more information about USB plug sockets, call our experienced staff on 01709 385485 or click here for more contact details.

Related content

How to choose a USB charger for the office

USB charger FAQs

Power module guide