If that’s correct, great—you’ll see content tailored for your region. If not, you can easily change your location below to access the most relevant products, specifications, and support.
A lift key switch may appear to be a simple component, but specifying the wrong one can cause installation delays, commissioning failures and compliance issues. This guide explains everything you need to know.
1. What is a Lift Key Switch?
A key switch is an electromechanical control device installed in a lift’s landing station, car operating panel or fixture. Turning a key rotates a lock barrel, which actuates a set of electrical contact blocks to open or close circuits.
This is how authorised personnel control functions that passengers should not be able to access; things like enabling attendant mode, bypassing fire safety interlocks, switching lighting circuits, activating fan control or transferring car operation.
Unlike a pushbutton, a key switch requires physical possession of the correct key to operate. That makes it a critical security and compliance component in any installation, particularly in buildings where lift access needs to be restricted or where fire service operation must meet EN81-72 requirements.
2. How to Order a Key Switch?
A Dewhurst key switch is a precision-engineered assembly, understanding what’s inside helps you understand why the ordering options exist; and why getting them right matters for long-term reliability.
2.1 Shape
Start with the shape, because the key switch has to sit alongside the pushbuttons in the same car operating panel or landing operating panel. The switch should match the rest of the fixture. This one decision keeps the whole panel looking like a single considered design. Dewhurst key switches are available in obround (US89), square (US90) and round (US91) formats to match the pushbutton ranges.
2.2 Depth
Match the space behind the panel to the series:
2.3 Specification
This is the heart of the specification, and the question that trips people up most often. It breaks into two parts.
2.3.1 Movement: does it stay, or spring back?
A standard movement stays where you turn it. Turn to 90 degrees and it holds there until you turn it back. Use it for functions that need to stay on or off, such as a fan or a light.
A spring return is captive: turn it and, on release, it snaps back to the 0 degree rest position automatically. Use it for momentary functions such as a pit reset (or a call send), where you want an action to happen but you do not want the switch to latch on.
2.3.2 Lock Barrel: which type do you want?
The choice of barrel determines the key type:
Standard flat key —widely used for general lift functions such as car preference, lighting and fan control
F1 — key removable at 0° only; the key cannot be taken away while the switch is on
F2 — key removable at both 0° and 90°; can be taken away whether on or off
High-security radial round key —harder to duplicate, preferred for restricted-access or sensitive functions
R1 to R6 — round key equivalents with different release combinations
Fireman’s triangular key —meets EN81-72 §5.8.1, required for fire service operation in compliant buildings
FR — Fireman’s triangular key, available in standard depth or low profile
2.3.3 Key Number
As standard, Dewhurst provides key number 827 for flat keys and key number 37001 for radial keys. If you require a different key number, please contact us.
2.3.4 Contact Configuration
Below are some common key switch applications:
Each configuration defines the electrical state of terminal pairs at each key position. O means Open, the circuit is off. C means Closed, the circuit is on. The three below cover the most common movements above:
2.4 Finish & Extras
With shape, series and function decided, two optional extras finish the specification.
2.4.1 Front finish
The face visible in the panel. Four finishes are available, all engineered to match the Dewhurst pushbutton ranges so the panel reads as one design.
2.4.2 Marking and illumination
Laser marking is only available on round (US91) format switches; black on stainless steel and brass, white on black plastic. Standard function labels include LIGHT, FAN, ATT, CAR PREF, PARK/RES, FIRE, TEST, PARK, DOOR HOLD and FLOOR.
LED halo illumination (code H24) adds a red LED ring around the keyhole, available on flat key variants across the Standard and Weatherproof ranges.
3. Putting it together: the order code
Answer the four questions and the code assembles left to right. Shape, then finish, then any halo, then key type and release, then contact arrangement.
