Overview
D+H SDS 2 and SDS 3 systems are purpose-designed operating systems for compatible roof skylights used for natural ventilation and smoke extraction.
Unlike a conventional window actuator mounted directly between a frame and sash, an SDS system combines the electric drive with a mechanical lifting mechanism and a skylight-specific installation arrangement.
This allows the drive force to be transferred through the lifting arms in a controlled way while supporting large opening angles and reducing concentrated loads on the skylight frame and hinges.
The range includes:
- SDS 2 high-force skylight systems.
- SDS 2 single and synchronised set configurations.
- SDS 2 systems for 24 V DC or 230 V AC supply.
- SDS 3 modular skylight systems.
- SDS 3 systems for different installation-clearance dimensions.
- SDS 3 24 V DC and 230 V AC configurations.
SDS skylight systems at a glance
| System | Primary characteristics | Typical application |
|---|---|---|
| SDS 2 | High-force drive unit with skylight-specific mechanical installation set and opening angle up to approximately 172° | Compatible rooflights requiring strong, rapid opening for natural ventilation and smoke extraction |
| SDS 3 | Modular low-profile skylight system with opening angles up to approximately 170° and installation-clearance options | Compatible skylights requiring an integrated modular system for daily ventilation and smoke extraction |
Complete skylight operating systems
The SDS range should be treated as a complete mechanical and electrical operating system rather than as a standalone actuator.
The system may include:
- Electric drive unit.
- Lifting arms and operating linkages.
- Skylight-specific installation set.
- Structural mounting rails and brackets.
- Control electronics.
- Position and status signalling.
- Emergency unlocking.
- Optional mechanical locking.
- D+H natural ventilation or smoke control panel.
The exact configuration depends on the skylight manufacturer, opening dimensions, lid weight, hinge arrangement, required opening angle, wind load, snow load and smoke control requirements.
SDS 2 skylight drive systems
The SDS 2 is a high-force skylight operating system designed for compatible rooflights used for natural ventilation and smoke extraction.
The system consists of a drive unit and a skylight-specific mechanical installation set.
The operating mechanism is structurally arranged to transfer the load through the lifting linkage while reducing concentrated strain on the skylight frame and hinges.
The SDS 2 can open compatible rooflights to approximately 172°, providing a large free opening for smoke exhaust or natural ventilation.
SDS 2 performance features
- Opening and closing of compatible skylights.
- Suitable for natural ventilation and smoke extraction applications.
- High-force push and pull operation.
- Approximately 172° maximum opening angle on compatible systems.
- BSY+ motor and microprocessor-controlled synchronisation.
- Single and synchronised set configurations.
- 24 V DC and 230 V AC versions.
- Skylight-specific installation sets.
- Pre-assembled mechanical modules.
- High IP64 protection for the drive unit.
- Tested operating life for ventilation and smoke extraction cycles.
SDS 2 technical data
| Model | SDS 2-DU-24V | SDS 2-DU-230V |
|---|---|---|
| Supply | 24 V DC ±15% | 230 V AC, +10% / -15% |
| Nominal input | 4 A | 145 VA |
| Push force | 3000 N | 3000 N |
| Pull force | 3000 N | 3000 N |
| Nominal locking force | 2200 N | 2200 N |
| Opening speed | 7.1 mm/second | 7.1 mm/second |
| Closing speed | 7.1 mm/second | 7.1 mm/second |
| Service life | 20,000 double strokes | 20,000 double strokes |
| Ingress protection | IP64 | IP64 |
| Temperature range | -5°C to +75°C | -5°C to +75°C |
| Fire stability | B300 — 30 minutes at 300°C | B300 — 30 minutes at 300°C |
| Weight per drive unit | Approximately 18 kg | Approximately 18 kg |
| Connection | 2.5 m silicone cable | 2.5 m silicone cable |
The published SDS 2 performance data references wind load class 1500 Pa and snow load class 500 Pa for a compatible 2.25 m² dome arrangement. Actual loads change with skylight size, weight and construction, and the skylight itself must be designed for the applicable loads.
SDS 2 single and synchronised set configurations
SDS 2 systems are available as individual drive units and as synchronised sets.
The set versions use two drive units and require two applicable skylight installation sets.
| Configuration | Supply | Drive arrangement | Published system weight |
|---|---|---|---|
| SDS 2-DU-24V | 24 V DC | Single drive unit | 18 kg |
| SDS 2-DU-230V | 230 V AC | Single drive unit | 18 kg |
| SDS 2-DU-24V-Set | 24 V DC | Synchronised two-drive set | 36 kg |
| SDS 2-DU-230V-Set | 230 V AC | Synchronised two-drive set | 36 kg |
The required number of drives depends on the skylight dimensions, lid construction, operating load, installation-set design and required system performance.
SDS 2 operating life
The SDS 2 product range has been assessed with at least 20,000 opening cycles for ventilation and an additional 1,000 opening cycles for smoke extraction in accordance with the referenced EN 12101-2 test basis.
The published 20,000-double-stroke service life relates to the drive unit. Continued system performance also depends on the condition of the skylight, hinges, seals, brackets and mechanical lifting components.
SDS 3 modular skylight systems
The SDS 3 is a compact modular skylight system for daily natural ventilation and smoke extraction.
It is designed to fit within the skylight upstand and can be configured to suit different installation-clearance dimensions.
The SDS 3 provides opening angles up to approximately 170°, with the maximum opening position adjustable using D+H SCS software.
The system includes integrated emergency unlocking and can be expanded with additional modules, project-specific installation components and optional mechanical locking.
SDS 3 installation sizes
| Model family | Nominal installation-clearance range | Typical supply options |
|---|---|---|
| SDS 3-0800 | 800 to 999 mm | 24 V DC or 230 V AC |
| SDS 3-1000 | 1000 to 1200 mm | 24 V DC |
| SDS 3-1200 | 1201 to 1400 mm | 24 V DC |
The SDS 3 system can also be expanded with project-specific modules and installation arrangements for dimensions up to approximately 2 m, subject to D+H system selection.
SDS 3 technical comparison
| Model | SDS 3-0800-1 | SDS 3-0800-5 | SDS 3-1000-1 | SDS 3-1200-1 |
|---|---|---|---|---|
| Supply | 24 V DC ±15% | 230 V AC, +10% / -15% | 24 V DC ±15% | 24 V DC ±15% |
| Electrical input | 4 A | 147 VA | 4 A | 4 A |
| Maximum opening force including snow load | 1980 N | 1980 N | 2200 N | 2200 N |
| Maximum closing force | 450 N | 450 N | 500 N | 500 N |
| Nominal locking force at lifting arm | 3000 N | 3000 N | 3400 N | 3400 N |
| Opening time | Approximately 60 seconds | Approximately 60 seconds | Approximately 60 seconds | Approximately 60 seconds |
| Closing time | Approximately 60 seconds | Approximately 60 seconds | Approximately 60 seconds | Approximately 60 seconds |
| Service life | 11,000 double strokes | 11,000 double strokes | 11,000 double strokes | 11,000 double strokes |
| Ingress protection | IP54 | IP54 | IP54 | IP54 |
| Temperature range | -5°C to +75°C | -5°C to +75°C | -5°C to +75°C | -5°C to +75°C |
| Fire stability | B300 | B300 | B300 | B300 |
| Weight | 18.5 kg | 18.5 kg | 18.5 kg | 19 kg |
SDS 3 lifting and locking arrangement
The SDS 3 mechanical lifting system supports the skylight through a structured linkage rather than applying the actuator force at a single isolated point.
The system provides a nominal locking force at the lift arm of up to 3000 N or 3400 N, depending on the selected model.
An optional mechanical locking arrangement is available for applications requiring additional resistance to wind loads or unauthorised opening.
Emergency unlocking is included in the basic system so the skylight can be released for service or emergency access in accordance with the applicable installation arrangement.
Large opening angles
SDS systems are designed to provide large skylight opening angles for effective natural ventilation and smoke extraction.
- SDS 2 systems can achieve approximately 172° on compatible skylights.
- SDS 3 systems can achieve opening angles up to approximately 170°.
- SDS 3 maximum opening angles can be adjusted using D+H SCS software.
The final opening angle depends on the skylight, hinges, upstand, installation set, clearances and mechanical configuration.
Wind and snow load coordination
Roof skylight drives must be selected for the combined skylight and environmental loads.
System review should include:
- Skylight lid weight.
- Snow load acting on the rooflight.
- Positive and negative wind pressure.
- Skylight area.
- Hinge position.
- Opening direction.
- Mechanical leverage through the opening cycle.
- Required opening angle.
- Frame and upstand strength.
The published SDS load values are based on defined test arrangements. They should not be transferred directly to a different skylight size or construction without reviewing the complete system.
Natural ventilation operation
SDS systems can provide controlled daily natural ventilation through compatible roof skylights.
Control options may include:
- Manual ventilation switches.
- Room temperature control.
- Carbon dioxide or indoor air quality sensors.
- Building management system signals.
- Time schedules.
- Rain sensors.
- Wind sensors.
- Weather stations.
- Position control where supported.
Automatic weather closing is particularly important for roof openings exposed directly to rain and strong wind.
Smoke extraction operation
SDS systems may form part of compatible smoke and heat exhaust ventilation systems.
The complete smoke extraction configuration may include:
- Compatible roof skylight or smoke vent.
- SDS mechanical operating system.
- D+H smoke control panel.
- Fire alarm interface.
- Battery-backed power supply for applicable 24 V systems.
- Fire-rated or otherwise specified field wiring.
- Position and fault monitoring.
- Cause-and-effect programming.
- Commissioning and functional testing.
Compliance or approval applies to the complete skylight and operating arrangement rather than the SDS drive alone.
BSY+ synchronisation
BSY+ electronics provide synchronised operation where two SDS systems or drive units are required.
Synchronisation helps coordinate movement and load distribution across larger skylights.
System configuration may include:
- Drive addressing.
- Synchronised operating groups.
- Opening-position programming.
- Fault monitoring.
- Position signalling.
- Interaction with the selected D+H control panel.
EBSA provides D+H programming and commissioning support for compatible SDS systems.
SDS 3 signalling and communication
The SDS 3 electronic system can be expanded with modules for open and closed position signalling.
Available system functions may include:
- SA open-position signal.
- SZ closed-position signal.
- BSY+ synchronisation of two systems.
- Connection to an ACB Gateway.
- D+H SCS programming.
The required modules and interfaces should be selected during the control-system design.
Installation coordination
SDS systems require close coordination between the skylight manufacturer, roofing contractor, structural designer, electrical contractor and controls provider.
Before product selection, confirm:
- Skylight manufacturer and model.
- Clear opening dimensions.
- Overall lid dimensions.
- Lid weight.
- Glazing or dome construction.
- Hinge arrangement.
- Upstand dimensions.
- Available installation clearance.
- Required opening angle.
- Wind and snow loads.
- Natural ventilation or smoke extraction function.
- Control-panel and power-supply requirements.
- Access for installation and future maintenance.
System installation
The mechanical operating system must be secured to structural parts of the skylight and upstand capable of resisting the operating and environmental loads.
The supplied or selected installation set must match the specific skylight arrangement.
Installation should verify:
- Correct positioning of the lifting mechanism.
- Alignment of all linkage arms.
- Secure structural fixings.
- Free movement through the complete operating cycle.
- Clearance from glazing, seals and roof components.
- Correct electrical connection.
- Emergency unlocking access.
- Mechanical locking operation where provided.
- Weather sealing of all roof penetrations.
Commissioning
Commissioning should include:
- Mechanical inspection of the skylight and lifting system.
- Confirmation of skylight weight and operating condition.
- Testing through the full opening and closing cycle.
- Verification of the required opening angle.
- Drive-group and BSY+ configuration.
- SCS programming where applicable.
- Testing of open and closed position signals.
- Testing of emergency unlocking.
- Testing of optional mechanical locking.
- Rain and wind sensor testing.
- Fire alarm and smoke control interface testing.
- Recording of product references and final settings.
Applications
D+H SDS skylight systems may be used for compatible:
- Roof skylights.
- Smoke and heat exhaust roof vents.
- Natural ventilation rooflights.
- Glass or polycarbonate skylight lids.
- Single-drive rooflight systems.
- Synchronised dual-drive rooflight systems.
- Large-angle smoke extraction openings.
- Commercial, industrial and public-building roof ventilation systems.
Product downloads
| Model | Product data | Installation instructions |
|---|---|---|
| SDS 2-DU-24V |
Download SDS 2-DU-24V data sheet |
Download SDS 2 installation instructions |
| SDS 2-DU-230V |
Download SDS 2-DU-230V data sheet |
|
| SDS 2-DU-24V-Set |
Download SDS 2-DU-24V-Set data sheet |
|
| SDS 2-DU-230V-Set |
Download SDS 2-DU-230V-Set data sheet |
|
| SDS 3-0800-1 |
Download SDS 3-0800-1 data sheet |
Download SDS 3 installation instructions |
| SDS 3-0800-5 |
Download SDS 3-0800-5 data sheet |
|
| SDS 3-1000-1 |
Download SDS 3-1000-1 data sheet |
|
| SDS 3-1200-1 |
Download SDS 3-1200-1 data sheet |
Frequently asked questions
What is an SDS skylight system?
An SDS system combines an electric drive with a purpose-designed mechanical lifting mechanism and a skylight-specific installation arrangement.
It is designed to open and close compatible roof skylights for natural ventilation or smoke extraction.
What is the difference between SDS 2 and SDS 3?
SDS 2 is a high-force system using a separate drive unit and mechanical installation set, with single and synchronised set versions.
SDS 3 is a compact modular lifting system designed around defined installation-clearance ranges and expandable project-specific components.
How far can an SDS system open a skylight?
SDS 2 systems can open compatible skylights to approximately 172°.
SDS 3 systems can provide opening angles up to approximately 170°, with the maximum position programmable using D+H SCS software.
Can SDS systems be used for daily ventilation?
Yes. Both SDS 2 and SDS 3 may be integrated with compatible natural ventilation controls, sensors, weather stations and building-management interfaces.
Can SDS systems be used for smoke extraction?
Yes, within a compatible designed and tested smoke extraction arrangement.
The complete skylight, drive mechanism, installation set, control panel and project requirements must be reviewed.
Are 24 V DC and 230 V AC versions available?
Yes. SDS 2 is available in 24 V DC and 230 V AC versions, including synchronised set configurations.
The uploaded SDS 3 range includes 24 V DC models and a 230 V AC SDS 3-0800-5 configuration.
Can two systems operate one skylight?
Yes. Compatible SDS systems can use BSY+ synchronisation where two drive units or systems are required.
The complete skylight and electrical design must allow for the combined loads and power requirements.
Can the system operate under snow load?
The systems have published load capacities that include defined snow-load conditions.
Actual suitability depends on the skylight area, weight, construction and project snow load. The skylight itself must also be capable of resisting the applicable loads.
Does the SDS 3 include emergency unlocking?
Yes. Emergency unlocking is integrated into the SDS 3 basic system.
Can EBSA programme and commission SDS systems?
Yes. EBSA can assist with product selection, D+H control-panel integration, BSY+ configuration, SCS programming and commissioning coordination.
Related drive pages
- Specialty Drives: locking, door, side-hung and skylight drive systems.
- SHD Side-Hung Window Drives: synchronised drives for wide side-hung windows.
- Rack and Pinion Drives: robust linear drives for roof and façade openings.
- Window Automation: complete natural ventilation and façade automation systems.
Discuss a skylight automation application
Provide EBSA with the skylight manufacturer, opening dimensions, lid weight, hinge arrangement, upstand details, required opening angle, wind and snow loads and control requirements. We can review the complete application and coordinate the SDS mechanism, installation set, control system and commissioning requirements.
