Bosch D273THR User Manual

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Fire Alarm Systems | D273 Series Photoelectric Smoke and Smoke and Heat Detectors
D273 Series Photoelectric Smoke and
Smoke and Heat Detectors
 
www.boschsecurity.com
 
 
 
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12 VDC or 24 VDC input
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Designed for commercial or residential use
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Four-wire application
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Light-emitting diodes (LEDs) indicate the status of
the chamber, power, and alarm
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Removable terminal block to simplify wiring
connections
The D273 Series includes the following detector
models:
Model
Description
D273
Four-wire
D273IS
1
Four-wire with an isolated 135°F (57°C) heat sensor
and sounder
D273TH
Four-wire with 135°F (57°C) heat sensor
D273THC
Four-wire with 135°F (57°C) heat sensor and auxiliary
relay
D273THCS
1
Four-wire with 135°F (57°C) heat sensor, auxiliary
relay, and sounder
D273THE
Four-wire with 135°F (57°C) heat sensor and EOL
relay
D273THR
2
Four-wire with 135°F (57°C) heat sensor and trouble
relay
D273THS
1
Four-wire with 135°F (57°C) heat sensor and sounder
D273THES
1
Four-wire with 135°F (57°C) heat sensor, sounder,
and EOL relay
1
Sounders produce 85 dB at 10 ft (3 m).
2
The trouble relay indicates both Dirty Smoke Chamber and/or
Power Loss conditions.
Each of the D273 Series Detector models is UL Listed
and works with commercial fire protective signaling
and household fire warning systems. Each model
detects smoke particles produced during wood, paper,
and fabric combustion.
System Overview
The D273 Series Detector models use an infrared (IR)
LED light source and a silicon photodiode to measure
light in a chamber. A fine screen covers the chamber
to deter insects and reduce dust accumulation and
nuisance alarms.
During a fire, smoke particles reflect light onto the
photodiode. When the photodiode measurements
exceed the alarm threshold, the detector signals an
alarm condition. After the alarm condition clears,
interrupt power at the control panel to reset the
detector.