Description
The Knightsbridge BT9CTEMS is a 9W LED bulkhead with integrated 3-hour maintained emergency lighting and an adjustable microwave sensor. The 256mm diameter white polycarbonate housing carries an IP65 rating for both indoor and outdoor use, with IK08 impact resistance for areas where vandalism or accidental knocks are a concern. The colour temperature is user-selectable between 3000K warm white (665lm), 4000K neutral white (760lm), and 5700K daylight (700lm) via a switch on the LED driver tray.
Designed for commercial hallways, stairwells, car parks, external building perimeters and communal areas in multiple-occupancy buildings, the bulkhead combines automatic operation with emergency failover. The microwave sensor detects movement through non-metallic materials (including thin walls and partition panels), with adjustable detection range, lux threshold and hold time allowing the fitting to be tuned to specific installation conditions. In emergency mode the fitting provides 120lm output for 3 hours during a mains failure, operating in maintained, non-maintained or switched configurations depending on wiring.
The hinged LED gear tray allows access to the driver, emergency battery and sensor settings without removing the fitting from the wall or ceiling. The polycarbonate diffuser spreads a 110-degree beam across the mounting surface, while the Class II double-insulated construction removes the need for an earth connection during installation. The push-fit terminal block accepts standard twin-and-earth cable without requiring a screwdriver, and the low 74mm projection keeps the fitting close to the mounting surface in areas with restricted headroom.
The LED array is rated at 60,000 hours to L70B50 (the point at which 50% of installations will have degraded to 70% of initial lumen output), giving approximately 20 years of life at 8 hours daily operation. The emergency battery is excluded from the 3-year warranty and requires replacement every 3-4 years depending on test frequency and discharge cycles.
Specification
| Diameter |
256 mm |
| Projection |
74 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 |
60000 |
| Energy Rating (Class) post 2021 SLR |
D |
| Beam Angle |
110 |
| CCT |
3000/4000/5700 K |
| Light Colour |
CCT |
| Lumens |
665 / 760 / 700 lm |
| Lumens (Light Source only) |
1070 lm |
| Lumens (Em. mode) |
120 lm |
| Wattage |
9 |
| Efficacy |
131 lm/W |
| CRI |
>85 |
| Driver Type |
Constant Current |
| Warranty |
3 |
| Warranty Information |
(excluding battery) |
Downloads
Product Specification Sheet
Frequently Asked
How is the colour temperature changed?
The CCT is adjusted via a selector switch on the hinged LED gear tray. Open the tray, set the switch to 3000K, 4000K or 5700K, close the tray and restore power. The setting persists through power cycles.
How does the microwave sensor work?
The sensor detects movement through microwave emission, which passes through non-metallic materials including thin plasterboard walls. Detection range, lux threshold (the ambient light level below which the sensor activates) and hold time (how long the light stays on after the last detected movement) are all adjustable via potentiometers on the driver tray.
What emergency modes are supported?
The fitting can be wired for maintained (always lit during mains operation, switches to emergency battery during power failure), non-maintained (only lights during power failure), or switched maintained (controlled by a switch during normal operation, automatically lights during power failure). The wiring configuration determines which mode is active.
Can it be used in wet locations outdoors?
Yes. The IP65 rating protects against water jets from any direction, making the bulkhead suitable for external walls, canopies, car parks and other covered outdoor areas. The IK08 impact rating provides resistance to vandalism and accidental knocks in public or semi-public areas.