Ultraviolet Flame Detector

Brand: BOSCH

Country of Origin: GERMANY

Model : D-284

Features:

• Highly reliable, long-lasting ultraviolet (UV) receptor tube

• Low power consumption

• Can be mixed with other detector types on the

control panel's initiation detection circuit (IDC)

• Easily maintained; can be cleaned without

Disassembly

Use the D284 wherever fires can develop quickly.

Suitable applications are:

• Petroleum storage areas
• Photographic or film storage areas
• Computer rooms
• Print shops
• Museums

Notice

The D284 is not a substitute for smoke or heat

detectors. It provides an added level of

notification for fast flaming fires only.

Notice

This product is not UL Listed.

Functions:

Basic Operation

An ultraviolet-detector tube within the D284 absorbs

very weak ultraviolet (UV) light such as that emitted

from a flame and produces an electrical current. The

detector's electronic circuitry translates this current

into an alarm signal. A counter-current prevents alarm

signals from single‑pulse UV sources such as lightning

• or cosmic flares. Additionally, the circuit is tuned to

respond only to wavelengths from 185 nm to 300 nm.

Coverage Area

The D284's response depends on both the size of the

fire and the distance from the fire to the detector;

therefore the effective coverage area varies. Very small

fires must have a duration of at least 7 sec if within

12 ft (3.7 m) of the detector and a duration of 30 sec

if within 12 ft to 25 ft (3.7 m to 7.6 m) of the detector.

Technical specifications:

Environmental Considerations

Relative Humidity: up to 95%, non-condensing at +104°F

(+40°C)

Temperature (operating): +14°F to +122°F (-10°C to +50°C)

Mechanical Properties

Color: Ivory

Dimensions (diameter x H) 4 in. x 2 in. (10.2 cm x 5.1 cm)

Material: ACS plastic (acrylonitrile-chlorinated

PE-styrene)

Output

Contact Rating: 260 mA at 24 VDC

Power Requirements

Current

Alarm: 0.25 mA at 24 VDC

Standby: 0.2 mA at 24 VDC

Voltage (operating)

Nominal: 24 VDC

Range: 17.6 VDC to 27.7 VDC

Response

Detection Angle: 120° conical

UV Sensitivity: 185 nm to 300 nm