Powering one office desk is relatively straightforward. Powering a bank of desks needs more planning.
Once several workstations are positioned together, the power system needs to consider where electricity enters the furniture, how it is distributed between desks, how many sockets are connected to each supply and how the cables will be routed without creating a tangle underneath the workstations.
Modular GST18 connections can make this much easier, but the objective should not simply be to connect as many desks as possible to one mains plug.
The complete furniture power system needs to be planned around the equipment, electrical supply and applicable requirements.
Start with the number and layout of workstations
Before deciding how to distribute power, establish exactly what the furniture layout looks like.
For example, are you powering:
- Two desks positioned back to back
- A four desk bench
- A six person workstation
- A long bank of individual desks
- A meeting or collaboration table
- Several separate desk clusters within the same room
The physical layout determines where power can enter the furniture and how far cables need to travel.
It can also help determine whether one furniture power system is appropriate or whether the desks should be divided between several separate mains supplies.
Do not start with the distribution block
A common temptation with modular power is to start by looking at how many outputs a distribution unit has.
That is the wrong way around.
A GST18 distribution unit provides connection points. It does not create additional electrical capacity.
You should first establish what needs to be powered and how the complete furniture electrical system will be configured.
Only then should you decide which mains leads, interconnecting cables or distribution components are required.
One 13A plug does not mean unlimited desk power
A standard UK 13A mains connection has a finite electrical capacity.
Adding a distribution block with several outputs does not change that.
The same applies to GST18 interconnecting leads. They allow compatible components to be connected together, but they do not increase the amount of power available from the original supply.
This is particularly important when several workstations are grouped together.
A modular system can make it physically possible to connect numerous components, but the electrical design still needs to remain suitable for the complete installation.
BS 6396 limits need to be considered
BS 6396:2022 specifies requirements for electrical power, data and telecommunications distribution systems incorporated into furniture.
For socket outlets connected to a single supply, the standard provides configurations based on the protection applied to each outlet.
The commonly used configurations are:
- No more than four socket outlets where each is protected at no more than 5A
- No more than six socket outlets where each is protected at no more than 3.15A
USB charging and other extra low voltage equipment also need to be considered as part of the complete system.
This means the question should not simply be, “How many desks can I connect to one plug?”
The number of mains sockets, their protection, USB charging and the overall furniture power configuration all matter.
For a fuller explanation, see our BS 6396:2022 guide.
Think in power systems rather than individual desks
When several desks are grouped together, it can help to think of each mains supply as feeding a furniture power system.
For example, rather than looking at a six desk bench and assuming every workstation must connect to the same 13A plug, divide the furniture into sensible electrical groups.
The appropriate arrangement will depend on:
- The number of mains sockets required
- The protection used within the desk power units
- The amount of USB charging
- The equipment being connected
- The position of available building power supplies
For larger layouts, more than one incoming mains supply may be required.
What role does a GST18 mains lead play?
A 13A to GST18 mains lead provides the connection between a standard UK socket and a compatible furniture power system.
Different lead lengths allow the incoming cable to be selected around the actual workstation layout.
For multiple desks, first decide where each furniture power system begins.
Then select a suitable mains lead length between that point and the building supply.
Avoid automatically choosing the longest cable available. Excess cable still needs to be supported and managed underneath the furniture.
What does a GST18 interconnecting lead do?
A GST18 interconnecting lead connects compatible furniture power components together.
Unlike the mains lead, it does not have a UK plug.
It can be useful where compatible components are positioned apart from each other within a furniture layout.
This allows the cable length between components to be selected according to the desk arrangement.
Our GST18 connection guide explains the difference between mains leads, interconnecting cables and distribution units in more detail.
When is a GST18 distribution unit useful?
A distribution unit is useful when one suitable incoming connection needs to branch to more than one compatible component.
Desktop Power supplies GST18 distribution options including:
- 1 input to 2 outputs
- 1 input to 5 outputs
These provide a tidy way to create several connection points from one incoming GST18 feed.
However, the number of physical outputs on the distribution block must not be confused with the number of mains sockets that can safely or appropriately be operated from the incoming supply.
The complete system still needs to comply with the relevant electrical requirements.
A five output distribution unit does not automatically mean five desks
This is an important distinction.
A distribution unit with five outputs simply provides five connection points.
If every connected desk power unit contained two mains sockets, connecting five of them would create ten socket outlets.
You cannot determine whether that arrangement is appropriate merely by counting the available GST18 connections.
Socket protection, USB charging, connected equipment and the requirements of the complete furniture power system need to be considered first.
How should a four desk bench be approached?
Imagine four employees sitting around a shared bench.
Each workstation may need:
- Permanent power for monitors or docking equipment
- Accessible mains power
- USB-C charging
The first step is not to order four identical power modules and connect them together.
Instead, establish the total number of mains outlets and charging connections required across the bench.
You can then decide how those requirements should be divided between one or more furniture power systems.
The result might involve separate mains feeds serving different sections of the bench rather than one connection supplying the entire group.
Accessible power does not need to supply permanent equipment
As with an individual workstation, permanent and temporary equipment can be separated.
Monitors and docking stations may be supplied beneath the desk, while users have accessible mains power and USB-C charging at worktop level.
For example, our Malmo under desk power unit can provide concealed connections for fixed equipment.
A suitable on desk or in desk unit can then provide the connections employees actually need to reach.
This approach can reduce the number of permanent plugs occupying accessible desktop sockets.
Do not forget the equipment load
Socket count is only one part of the calculation.
The electrical demand of the connected equipment matters as well.
Normal office equipment such as monitors, computers and docking stations is very different from high power appliances.
A spare socket within an office furniture power system should not be treated as an invitation to connect any appliance that happens to use a UK plug.
Equipment that falls outside the intended workstation use may require a separate suitable supply.
Keep the mains entry points organised
Multiple desk installations can become messy when every power lead takes a different route across the floor.
Where possible, establish defined power entry points for each furniture group.
This can help keep the installation organised and make it easier to identify which incoming supply serves which section of furniture.
The exact layout will depend on the building and may use wall sockets, floor boxes or other suitable supplies.
Plan cable lengths around the actual desk layout
One of the advantages of GST18 connections is that the mains and interconnecting lead lengths can be selected separately.
Use that flexibility.
For each connection, consider:
- The actual distance between components
- The route the cable needs to follow
- Any cable baskets or trays
- The position of the furniture power components
- Whether the desk is height adjustable
- A sensible allowance without excessive loose cable
This is usually better than purchasing one cable length for the entire project and trying to hide whatever is left over.
Cable baskets work particularly well with desk banks
When several desks are grouped together, horizontal cable management becomes especially useful.
A wire basket underneath the work surface can support:
- GST18 mains leads
- Interconnecting cables
- Monitor leads
- Data cables
- Docking station power supplies
- Excess cable length
Keeping these cables supported underneath the desk prevents them simply hanging below the workstation.
Plan the vertical cable route too
Eventually, each furniture power system needs to connect back to the building supply.
The route between the underside of the desk and the floor therefore needs to be considered.
Depending on the furniture, this might use a cable spine or cable wrap from our cable management range.
Our Desk Cable Management Guide covers horizontal and vertical routing in more detail.
Height adjustable desk banks need additional care
If several sit stand desks are grouped together, each moving work surface needs a cable route that can accommodate its full range of movement.
A cable should not be stretched between two desks that can move independently.
Each moving section needs to be planned around its own equipment and cable movement.
Check the furniture at minimum and maximum height before finalising the installation.
Do not rely on daisy chaining simply because the connectors allow it
Modular connectors make linking components convenient, but physical compatibility is not a substitute for electrical planning.
Before connecting one furniture component through another, confirm that the products and overall configuration are intended for that use.
The total socket provision, protection, charging load and electrical supply all need to remain appropriate.
This becomes increasingly important as the number of connected desks grows.
Create a simple power schedule for larger desk groups
For an office with several desk banks, a simple schedule can make ordering much easier.
| Desk group | Workstations | Power requirement | Mains feed |
|---|---|---|---|
| Bench A | 4 desks | Record total sockets and charging | Define required furniture power systems |
| Bench B | 6 desks | Record total sockets and charging | Define required furniture power systems |
| Meeting Room | 8 seats | Temporary power and USB-C | Plan separately |
For each group, record the required mains leads, interconnecting cables, distribution components and cable management.
This is much easier to check than treating every cable and power unit as an unrelated item.
A multiple desk power checklist
Before ordering power for a group of desks, confirm:
- The number of workstations
- The total number of mains sockets required
- The protection used within the furniture power system
- The USB-C charging requirement
- The equipment being connected
- The number of incoming mains supplies required
- Where each furniture power system begins
- The GST18 mains lead lengths
- Any interconnecting cable requirements
- Whether distribution units are required
- The horizontal cable route
- The vertical cable route
- Any height adjustable furniture
- BS 6396 requirements for the complete system
Neat power starts with sensible distribution
GST18 products make it much easier to create modular office furniture power systems, particularly when several desks are grouped together.
The key is to use that flexibility to organise the installation rather than simply adding more connections.
Start with the furniture layout and equipment requirements. Work out the socket and charging provision. Decide how many suitable mains supplies are needed. Then select the GST18 leads, distribution components and cable management required to connect everything together.
That creates a much more practical system than starting with a distribution block and seeing how many desks can be attached to it.
Important: This article provides general guidance for office furniture power planning and is not an electrical design specification. Electrical furniture systems should be specified and installed appropriately for the intended equipment, supply and applicable standards. Refer to the current BS 6396 standard and seek suitable professional advice for specific installations.