120-8 January, 2016
Model F120 UV/IR Flame Detector
Alarm and Delayed Alarm
The Model F120’s standard conguration requires at least two of its three sensors to be
activated to signal an alarm. When ame radiation is initially detected, the Alarm outputs,
both relay contact and current loop, are instantly activated. A red LED alarm light behind the
viewing window in the detector is also activated. The detector has a default Delayed Alarm
setting of six seconds to conrm a ame has been detected. Should this ame persist for
this period of time, the Delayed Alarm output (relay and current loop) will be activated. The
Delayed Alarm setting can also be changed from six seconds to three seconds to provide a
rapid response time.
Automatic Self-Check (ASC)
Periodically, the Model F120 Flame Detector runs the Automatic Self-Check program. A
source of UV radiation is transmitted, via a sapphire rod to the outside surface of the viewing
window, and then passes through the window onto the sensor element. This test ensures
that the sapphire window is clear of any obstruction and that the sensors inside the detector
are functioning properly. Should the transmission of the window be degraded, or other circuit
malfunctions detected, the yellow Malfunction LED in the detector will turn on, the malfunction
relay contacts will transfer, and the 0-20 mA output will transmit a malfunction signal. This
malfunction indicates a need for maintenance before the performance has been degraded
enough to prevent response to ame.
.
To Next Page
Loading...