Справочник Пользователя для Bosch D255
Fire Alarm Systems | D254/D255 Fixed-temperature Heat Detector Heads
D254/D255 Fixed-temperature Heat
Detector Heads
www.boschsecurity.com
u
Mounts on low-profile six-inch diameter base
u
Easy head removal for cleaning and servicing
u
Available in 135°F (57°C) or 190°F (88°C) fixed
settings
settings
u
Optional latching alarm LED
u
Tamper-resistant locking base
Use the D254 and D255 Fixed Temperature Heat
Detectors for indoor confined areas where a fire
increases air temperature slowly and where there is a
substantial increase in air temperature before the fire
breaks confinement. Furnace rooms, closets,
bathrooms, and other confined areas are appropriate
applications for fixed temperature detectors.
Detectors for indoor confined areas where a fire
increases air temperature slowly and where there is a
substantial increase in air temperature before the fire
breaks confinement. Furnace rooms, closets,
bathrooms, and other confined areas are appropriate
applications for fixed temperature detectors.
Notice
These heat detectors are intended for detection
circuits that protect property. Use smoke
detectors to protect personnel.
These heat detectors are intended for detection
circuits that protect property. Use smoke
detectors to protect personnel.
Use the D254 (response-rated at 135°F [57°C]) in
areas where the ambient temperatures do not exceed
100°F (38°C). Use the D255 (response-rated at 190°F
[88°C]) in areas where the ambient temperatures do
not exceed 150°F (66°C).
These detectors operate in 12 and 24 VDC detection
circuits using a variety of Bosch detector bases. A
latching steady-on LED is available when these heads
are used with the D253 24 VDC base or the D271S
12 VDC base.
areas where the ambient temperatures do not exceed
100°F (38°C). Use the D255 (response-rated at 190°F
[88°C]) in areas where the ambient temperatures do
not exceed 150°F (66°C).
These detectors operate in 12 and 24 VDC detection
circuits using a variety of Bosch detector bases. A
latching steady-on LED is available when these heads
are used with the D253 24 VDC base or the D271S
12 VDC base.
Functions
Detector Head and Base System
These heat detectors have two components: the
detector base and the detector head. The bases are
permanently attached and wired to back boxes. The
interchangeable heads quickly detach for replacement
and cleaning without affecting the circuit wiring.
detector base and the detector head. The bases are
permanently attached and wired to back boxes. The
interchangeable heads quickly detach for replacement
and cleaning without affecting the circuit wiring.
Detection Method
These heat detectors use a push‑rod activated by a bi-
metal disk to manually close internal contacts and
initiate an alarm condition. The disk, which deflects at
a pre‑determined temperature, snaps back to its
original shape when the temperature drops, opening
the contacts and canceling the alarm signal.
This simple design results in stable detectors that are
dependable and have a long operational life. They are
unaffected by barometric pressure and air flow and
remain reliable over a wide range of conditions.
metal disk to manually close internal contacts and
initiate an alarm condition. The disk, which deflects at
a pre‑determined temperature, snaps back to its
original shape when the temperature drops, opening
the contacts and canceling the alarm signal.
This simple design results in stable detectors that are
dependable and have a long operational life. They are
unaffected by barometric pressure and air flow and
remain reliable over a wide range of conditions.