If you are specifying power for office desks, you will probably come across the term GST18.
GST18 connections are commonly used within modular office furniture power systems. They allow compatible desk power units, mains leads and distribution components to be connected together without every power module requiring its own permanently attached UK plug and fixed length cable.
At Desktop Power, GST18 connections are used across many of our desk power products and accessories.
This guide explains what the connection does, the difference between the main types of GST18 power lead and how the components fit together in a typical office workstation.
What is a GST18 connection?
GST18 is a compact plug and socket style connection used in modular electrical systems.
For office furniture power, the version you will commonly encounter is a three pole connection carrying live, neutral and earth.
Instead of running a fixed mains cable directly out of every desk power product, the power unit has a GST18 connection. A suitable mains lead or interconnecting cable can then be selected according to the furniture layout.
This modular approach is particularly useful for office desks, meeting tables and other furniture where cable lengths and power arrangements vary from one installation to another.
Are GST18 and Wieland the same thing?
You may see the terms GST18 and Wieland used together elsewhere in the office furniture market.
Wieland Electric produces the original GST connector system, but not every cable or connector described in the wider market as GST18 is a Wieland branded product.
The GST18 cables and connection products supplied by Desktop Power are not sold as Wieland branded products.
For that reason, we describe our products by their GST18 connection type rather than presenting them as genuine Wieland components.
When combining components, always use products that are specified as suitable for the system being installed. Mechanical fit alone should not be used as proof that products from different manufacturers are electrically or system compatible.
Why use GST18 for desk power?
The main advantage is flexibility.
Imagine a desk power unit with a permanently attached two metre mains cable.
That might be ideal for one workstation, but another desk could be half a metre from the building socket while a third might need a much longer cable route.
With a modular GST18 system, the desk power unit and mains cable can be selected separately.
This makes it easier to:
- Select a mains lead length to suit the desk
- Keep unnecessary cable length to a minimum
- Connect compatible power modules together
- Use distribution units where power needs to branch
- Plan power around different furniture layouts
- Replace individual cable components where appropriate
The four GST18 products you are most likely to encounter
For most office furniture installations, the basic components are straightforward.
| Component | Purpose |
|---|---|
| 13A to GST18 mains lead | Connects the furniture power system to a standard UK mains socket |
| GST18 interconnecting lead | Connects compatible power modules or components together |
| 1 in 2 out distribution unit | Splits one compatible GST18 feed into two outputs |
| 1 in 5 out distribution unit | Provides multiple outputs from one suitable incoming connection |
You can view these in our Power Leads, Connections and Distribution Blocks collection.
What is a GST18 mains lead?
The mains lead is the starting point for a simple desk power installation.
One end has a standard UK 13A plug. The other end has the appropriate GST18 connection for the compatible desk power unit.
This allows a product such as the Malmo under desk power unit to connect to a normal wall or floor socket without having a permanently attached mains cable.
Desktop Power supplies 13A to GST18 mains power cables in different lengths so the lead can be selected around the workstation layout.
Why does mains lead length matter?
Using an unnecessarily long power lead creates more cable that then has to be stored and managed underneath the desk.
A lead that is too short creates the opposite problem and may place tension on connections or simply fail to reach the intended mains outlet.
Before ordering, consider:
- The position of the desk
- The location of the nearest building power socket
- The route the cable will actually take
- Whether it will travel through a cable basket
- Whether the workstation is height adjustable
The shortest lead is not automatically the best option. There should still be enough length for a sensible cable route without placing strain on the connection.
What is a GST18 interconnecting power cable?
An interconnecting cable has GST18 connections at both ends and is designed to connect compatible parts of a modular power system together.
This is different from the mains lead because it does not have a UK 13A plug at one end.
A simple way to think about the two is:
- Mains lead: building power to furniture power system
- Interconnecting lead: one compatible furniture power component to another
Interconnecting leads are available in different lengths so connected components can be positioned according to the furniture layout.
What is a GST18 distribution unit?
Sometimes one incoming power connection needs to feed more than one compatible branch.
A distribution unit provides a compact way to divide the incoming connection into several outputs.
Desktop Power currently offers both a 1 in 2 out GST18 distribution unit and a 1 in 5 out distribution unit.
These can be useful where a furniture power layout contains several compatible modules that need to be supplied from a planned distribution point.
A simple GST18 workstation example
For a straightforward office workstation, the arrangement could be very simple.
- A UK mains socket supplies the workstation
- A 13A to GST18 mains lead connects to the furniture power system
- The GST18 connection supplies a Malmo under desk power unit
- Monitors and docking equipment plug into Malmo
- Accessible desktop power provides charging and temporary connections for the user
In this example, no distribution block or interconnecting lead may be necessary.
The modular connection simply allows the correct mains lead length to be used with the desk power module.
When would an interconnecting cable be useful?
An interconnecting cable becomes useful where compatible components need to be linked across the furniture installation.
For example, the desk layout may require power components to be positioned separately rather than immediately next to each other.
Instead of using a separate UK mains plug for every component, an appropriate modular system can use interconnecting cables as part of the planned furniture power arrangement.
The exact configuration must still be appropriate for the products and electrical system being installed.
When would you use a distribution block?
A distribution block is useful where the power route needs to branch.
For example, one incoming connection may need to supply more than one compatible module positioned around a furniture installation.
A 1 in 2 out unit provides two outgoing connection points, while a 1 in 5 out unit provides more outputs for larger arrangements.
This does not mean that simply adding a distribution block gives the electrical system more available power. It only changes how the existing supply is distributed between compatible components.
GST18 does not increase the available electrical load
This distinction is important.
GST18 is a connection system. It does not create additional electrical capacity.
The amount of equipment that can be connected still depends on the supply, protection, furniture power system and applicable electrical requirements.
Adding more connection points should therefore not be confused with increasing the available power.
What does male and female mean on a GST18 cable?
GST18 components use mating plug and socket connections.
You will often see these described as male and female connections when looking at power leads and interconnecting cables.
The important thing when ordering is not simply remembering which end is called male or female. Check the actual input and output required by the products being connected.
For example, an interconnecting cable is designed with the appropriate connection at each end to link compatible components, while a mains lead is configured to connect a UK plug to the GST18 input of the furniture power system.
Do GST18 connectors lock together?
GST18 style systems commonly use a locking arrangement to help prevent connections being unintentionally separated.
This makes them well suited to installations inside furniture where connections are intended to remain secure rather than being repeatedly unplugged by the workstation user.
They should not be treated like an everyday mains plug that is regularly connected and disconnected while equipment is in use.
Can you mix GST18 components from different manufacturers?
This needs care.
Products may look physically similar, but a connector fitting into another connector does not by itself prove that the two products have been tested or approved to operate together as a complete system.
Manufacturers of installation connector systems specifically warn against assuming cross manufacturer compatibility purely from mechanical fit.
If you are extending an existing furniture power installation, establish what system is already installed and confirm that any additional components are suitable for use with it.
How does GST18 relate to BS 6396?
GST18 is the connection method used between components. BS 6396 relates to the wider electrical system incorporated into furniture.
For an office furniture installation, the complete system matters, including:
- The incoming electrical supply
- Protection
- Desk power units
- Under desk distribution
- Power leads and connections
- Socket provision
- Cable routing
- Inspection and testing
A GST18 connector should therefore not be viewed as proof that an installation complies with BS 6396.
For more information on furniture power requirements, read our BS 6396:2022 guide.
GST18 and cable management should be planned together
One of the advantages of choosing separate mains and interconnecting leads is that cable lengths can be selected around the furniture layout.
However, the cables still need to be supported and routed correctly.
A cable basket, cable spine or cable wrap can help keep the power route controlled around the workstation.
Our Desk Cable Management Guide explains this part of the installation in more detail.
A simple GST18 ordering checklist
Before ordering components for a workstation, check:
- Which desk power products are being connected
- The connection type used by each product
- Whether a mains lead is required
- The required mains lead length
- Whether any interconnecting leads are needed
- The distance between connected components
- Whether the power route needs to branch
- Whether a distribution unit is required
- How the cables will be supported underneath the desk
- Whether the components are suitable for use together
- The requirements of the complete furniture power installation
Why GST18 works well for office furniture
The main benefit of GST18 connections is modularity.
The power module does not dictate the length of the mains cable, and compatible components can be positioned around the furniture rather than everything having to terminate at a separate wall socket.
For a simple desk, that may mean nothing more complicated than selecting the correct 13A to GST18 mains lead for a Malmo power unit.
For a larger furniture installation, interconnecting leads and distribution blocks can form part of a more structured power layout.
The important part is to plan the whole power route rather than treating each cable and connector as an isolated accessory.
Important: This article provides general information about modular office furniture power connections. GST18 is used in the market to describe this connector format, but products from different manufacturers should not automatically be assumed to be compatible. Electrical furniture systems should be specified and installed appropriately for the products, supply and applicable standards.