Description
The Knightsbridge BT20ACTEMS is a 20W LED bulkhead with switchable colour temperature (3000K warm white, 4000K neutral white, 5700K cool daylight), a 3-hour maintained emergency function, and an adjustable microwave sensor for occupancy detection. The 380mm diameter white polycarbonate housing carries an IP65 rating for dust and water ingress protection, making it suitable for both internal and external mounting on walls or ceilings.
Designed for corridors, car parks, storage areas, external building entrances and commercial spaces where emergency lighting, automated control and weatherproofing are all required, the bulkhead combines three functions in a single fitting. The microwave sensor adjusts for detection range, lux threshold and hold time, allowing the light to remain off during daylight hours and to switch on only when movement is detected in low-light conditions. The emergency mode provides 190 lumens for 3 hours during mains power failure, meeting maintained, non-maintained and switched emergency requirements.
The polycarbonate diffuser produces a 115-degree beam spread with output ranging from 1730 lumens at 3000K to 1930 lumens at 4000K depending on the CCT setting selected. The hinged LED gear tray allows access to wiring and the emergency battery without removing the entire fitting from the wall. The Class II double-insulated construction means no earth connection is required. The fitting achieves 125.7 lumens per watt at its most efficient CCT setting and carries a 5-year warranty excluding the emergency battery.
Specification
| Diameter |
380 mm |
| Projection |
81 mm |
| Construction |
Polycarbonate |
| Finish |
White |
| Class |
II |
| IP Rating |
IP65 |
| Primary Voltage |
230V 50Hz |
| Diffuser |
Opal |
| Emergency |
Maintained / Non-maintained / Switched |
| Lamp Technology |
SMD LED |
| Lamp Included |
Yes |
| Dimmable |
No |
| L70B50 |
50000 |
| Energy Rating (Class) post 2021 SLR |
E |
| Beam Angle |
115 |
| CCT |
3000/4000/5700 K |
| Light Colour |
CCT |
| Lumens |
1730 / 1930 / 1855 lm |
| Lumens (Light Source only) |
2190 lm |
| Lumens (Em. mode) |
190 lm |
| Wattage |
20 |
| Efficacy |
125.7 lm/W |
| CRI |
>80 |
| Driver Type |
Constant Current |
| Warranty |
5 |
| Warranty Information |
(excluding battery) |
Downloads
Product Specification Sheet
Frequently Asked
How is the colour temperature changed?
The CCT is switchable via a switch on the driver board accessed through the hinged gear tray. The three settings are 3000K warm white (1730lm), 4000K neutral white (1930lm) and 5700K cool daylight (1855lm). Set the temperature before final installation.
What does the microwave sensor control?
The microwave sensor detects movement within its range and switches the light on when motion is detected in low-light conditions. Detection range, lux threshold (daylight sensitivity) and hold time (how long the light stays on after motion stops) are all adjustable via controls on the sensor module inside the gear tray.
How does the emergency function work?
The fitting includes a 3-hour maintained emergency battery. In maintained mode the light operates normally on mains power and switches to battery power during a mains failure, continuing to provide 190 lumens for 3 hours. Non-maintained and switched emergency modes are also supported depending on wiring configuration.
Can it be used in wet outdoor locations?
Yes. The IP65 rating protects against dust ingress and low-pressure water jets from any direction, making the fitting suitable for external building entrances, covered walkways, car parks and similar semi-exposed locations. It is not submersible and should not be installed where it will be submerged or subjected to high-pressure washing.