Window actuator glossary

In this glossary we explain the most important technical terms related to electric window actuators, natural ventilation and smoke and heat exhaust. Short, clear and with practical examples.

Terms from A to Z

• 24 V or 230 V – which voltage for window actuators
• 24 V power supply – extra-low voltage for window actuators
• Octagonal shaft – winding shaft for roller shutters
• Trigger device – starts the SHEV (smoke detector, SHEV push button)
• Logbook (SHEV) – record of maintenance and inspections
• Outer frame and sash – fixed and moving part of the window
• CO₂ sensor – ventilating by air quality
• Pitched roof window – window in the roof slope
• Listed buildings – permit for changes to a listed building
• Double chain actuator – two chains for wide sashes
• Tilt-and-turn window – automating in tilt position
• Mounting position – where and how the actuator sits on the window
• Duty cycle (ED) – how long an actuator may run continuously
• Limit switch-off – automatic stop in the end position
• safety stay – secures the tilt sash against falling
• Window opener – opens windows by crank or motor
• Sash weight – estimating weight with a rule of thumb
• Radio remote control (433 MHz) – operate windows without a switch cable
• Hand-held transmitter – small radio remote for actuators
• Main closing edge and secondary closing edge – pinch points on the motorised window
• Lever arm – why the actuator position changes the force
• Obstacle detection – stop on resistance
• Stroke length – how far the actuator extends
• Box-type window – two windows one behind the other, typical of old buildings
• Chain actuator – window actuator with push chain
• Bottom-hung sash – hinged at the bottom, opens at the top
• Top-hung sash – hinged at the top, opens outwards
• Bracket – fastening the actuator to frame and sash
• Louvre window – many narrow blades instead of one sash
• Load cut-off – stop on obstacle or overload
• Running speed – how fast the actuator opens
• Cable cross-section – calculating cables for 24 V actuators
• Continuous rooflight – continuous rooflight in hall roofs
• Dome rooflight – rooflight in the flat roof
• Ventilation kit – actuator with matching controls
• Ventilation control – controls window actuators for ventilation
• Ventilation switch – OPEN/CLOSE wall switch
• Mechanical window opener – opening by handwheel or crank
• Modbus – data interface for smart actuators
• Night cooling – ventilate and cool automatically at night
• Emergency hand crank – operation during a power cut
• NRWG – natural smoke and heat exhaust ventilator
• Transom window – window in the upper part of a wall
• Opening width – how far the window opens
• Parallel opening window – sash pushed out in parallel
• Polarity reversal – changing direction on 24 V actuators
• Position feedback – reports whether the window is open or closed
• Certified inspection expert – inspects safety systems such as SHEV
• Cross ventilation – airflow through opposite windows
• Smoke vent area – effective opening area of an SHEV
• Rain sensor – closes windows when it rains
• Tubular motor – drive for roller shutters, awnings and roller blinds
• RWA – smoke and heat exhaust ventilation system
• thrust force – how much force the actuator opens with
• Protection class (IP code) – protection against dust and water
• Pivot sash – turns around a horizontal axis
• Side-bend chain – chain that only bends sideways
• Sawtooth roof – saw-tooth roof with glazed faces
• Safety extra-low voltage (SELV) – why 24 V is safe
• Voltage drop – voltage loss on long 24 V cables
• Spindle drive (linear actuator) – actuator with threaded spindle
• Actuator (general term) – general term for window actuators
• Current consumption – sizing the power supply correctly
• Synchronous control – identical run of several actuators
• Tandem and synchronous operation – several actuators on one sash
• Temperature sensor – ventilating by temperature
• UPS – uninterruptible power supply during power cuts
• Concealed installation – actuator hidden in the window profile
• Locking drive – lock and unlock windows electrically
• Maintenance of window actuators – checklist
• Wind monitor – protection in storms
• Rack-and-pinion actuator – window actuator with rack
• Zigbee and Matter – radio standards for the smart home
• Holding force – force that holds the closed sash

Solutions by window type

• Open and retrofit tilt windows electrically
• Open and retrofit roof windows electrically
• Retrofit a rooflight with a motor

Actuator from another manufacturer defective? The Window actuator replacement table shows which Vent Systems actuator fits as a replacement for GEZE, D+H, Aumüller, SIMON, Nekos, Mingardi and others.

More terms will follow. Detailed instructions can be found in the Guide.

Not sure which actuator fits? Call us: 040 50694631 (Mon–Fri 8 am–5 pm) or use the actuator finder.