DETECTOR,FIRE PROTECTION,HEAT,725 DEG F,

FENWAL INCORPORATED:

12-X27120-020 <- This part number is not correct, please check attached datasheet.

Correct Part number: 27121-020-725

Detectors are 4 wire, N/O �?Closes at Rise,

Alarm temp: 725 °F = 385 °C

detectors are welded, fully stainless steel, hermetically sealed, leak tested in water

Customs tariff code: 85311030

Construction :
000 units have a Type300 stainless steel sensing shell and a brass mounting head, 002, 020, 003 and 005 units are all Type 300

DAF - Detect-a-Fire / Heat & Fire-Detector

DAF - Detect-a-Fire / Heat & Fire-Detector

DESCRIPTION
DETECT-A-FIRE® detectors are the “heart�?of many fire protection systems. These highly reliable devices have been the standard for
over 65 years. Thousands of these detectors are in use controlling the release of extinguishants such as clean agents, CO2, water, or
dry chemicals. In some systems the device is used as an ALARM device, to sense overheat or fire and alert personnel.
DETECT-A-FIRE detectors have met with wide acceptance because they are designed with RATE COMPENSATION. This provides
a unique advantage over both fixed temperature and rate-of-rise types of detectors because only the DETECT-A-FIRE detector
accurately senses the surrounding air temperature regardless of the fire growth rate. At precisely the pre-determined danger point,
the system is activated.
Fixed temperature detectors must be completely heated to alarm temperature and therefore a lag in response time may occur with a
fast rate fire. Rate-of-rise devices, on the other hand, are triggered by the rate of increase in ambient temperature and are subject to
false alarms caused by harmless, transient thermal gradients such as the rush of warm air from process ovens.
The key to the unit’s sensitivity is in the design (Figure 1). The outer shell is made of a rapidly expanding alloy which closely follows
changes in surrounding air temperature. The inner struts are made of a slower expanding alloy. Designed to resist thermal energy
absorption and sealed inside the shell, the struts follow temperature changes more slowly.
A slow rate fire (Figure 2) will heat the shell and struts together. At the “set point�? the unit will trigger, actuating the alarm or releasing
the extinguishant.
A transient rush of warm air up to 40°F/min. may expand the shell, but not enough to trigger the unit. By ignoring transient warm air
excursions, the DETECT-A-FIRE detector virtually eliminates false alarms prevalent with rate-of-rise devices.
If a fast rate fire (Figure 3) starts, the shell will expand rapidly. The struts will close, actuating the alarm and/or releasing the agent.
The faster the fire rate of growth, the sooner the DETECT-A-FIRE detector will react
Detect Over Heat before!
When there is a Fire it’s already too late...
H D L - 4
H D L - 3 - X L
H D L - 6
H D L - 7
C F D - I n c o n e l w i r e
H D L - 5
HDL-2 & HDL-3
Connection Houses
Linear Heat Detection
P r o t e c t i v e s h e l l s
& A c c e s s o r i e s