Switch
Contents |
[edit] Introduction
A ‘switch’ is typically an electrical device which can either be turned on or off, depending on whether the requirement is to activate an electric circuit (turn on) or close it (turn off). Switches can be used to turn on/turn off lights and other electrical appliances and are used for a myriad of other domestic, commercial and industrial applications; this includes changing TV channels, pressing the keys on a computer keyboard and activating/deactivating car door-opening mechanisms.
[edit] How it works
When a switch is turned on, an electrical circuit is completed, allowing electric current to flow, causing the activation of the desired effect (e.g to turn a light on). Closing the switch (off position) breaks the circuit and stops the effect in question.
[edit] Manual v automatic
Switches can be activated manually or automatically:
Manual-type examples:
Automatic-type examples:
- Central heating on-off timer.
- Automatic pump.
- Smoke alarm.
As there is usually no manual activation with automatic switches, there must be an agent that causes the switch to activate. In an automatic pump, for instance, that agent is water: when the water level reaches a predetermined level, it completes a circuit causing the pump to operate. When the water level drops, the circuit is ‘broken’ and the pump stops.
[edit] Toggle
Another type of switch is a ‘toggle’ – a manually activated switch that has a protruding lever which makes it easy to actuate banks of toggle switches that need to be activated or deactivated simultaneously.
[edit] Railroad switch
A ‘switch’ in the railway sector is a mechanical device that allows a railway track to be ‘switched’ from one position to another, thereby diverting a train onto a different track. This type of switch is sometimes referred to as ‘points’.
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
Gregor Harvie argues that AI is state-sanctioned theft of IP.
Many resources for visitors aswell as new features for members.
Using technology to empower communities
The Community data platform; capturing the DNA of a place and fostering participation, for better design.
Heat pump and wind turbine sound calculations for PDRs
MCS publish updated sound calculation standards for permitted development installations.
Homes England creates largest housing-led site in the North
Successful, 34 hectare land acquisition with the residential allocation now completed.
Scottish apprenticeship training proposals
General support although better accountability and transparency is sought.
The history of building regulations
A story of belated action in response to crisis.
Moisture, fire safety and emerging trends in living walls
How wet is your wall?
Current policy explained and newly published consultation by the UK and Welsh Governments.
British architecture 1919–39. Book review.
Conservation of listed prefabs in Moseley.
Energy industry calls for urgent reform.
Heritage staff wellbeing at work survey.
A five minute introduction.
50th Golden anniversary ECA Edmundson apprentice award
Showcasing the very best electrotechnical and engineering services for half a century.
Welsh government consults on HRBs and reg changes
Seeking feedback on a new regulatory regime and a broad range of issues.
CIOB Client Guide (2nd edition) March 2025
Free download covering statutory dutyholder roles under the Building Safety Act and much more.