574-442
Rev. B
The data reader displays a message (similar to the one shown in Figure 3) when
a compatible detector is scanned and a valid reading is made. The data shown as
“
20%ALM
” represents the value of the last smoke measurement in terms of
“percent to alarm”. For example, if the last measurement returned a value above
the factory set “Clean Air Value” and is half way to the factory set “Alarm
Threshold”, the display indicates “
50%ALM
.” Since the operator is scanning
the device in clean air, it is assumed that the increase in the smoke measurement
is due to contamination of the smoke sampling chamber.
Typically, increased contamination of the smoke sampling chamber
automatically leads to increased smoke sensitivity of the detector. However, in
this case, the Simplex TrueAlarm detector compensates for chamber
contamination. The TrueAlarm technique compensates up to 50% to alarm
(50%ALM), while maintaining the detector’s full factory set sensitivity. If left
uncleaned, any additional contamination results in increased smoke sensitivity.
Note:
The detector must be cleaned or replaced if it exceeds 50% to alarm
(50%ALM), or if both LEDs are illuminated.
The detector requires a full 24 hours to complete chamber compensation,
initially and if the device is reset, it returns to its factory set Alarm Threshold
value (see Figure 3). This leads to higher sensitivity initially, but as the
compensation proceeds the detector returns to its compensated sensitivity.
Interpreting the Data Reader’s
Display
Figure 3. Interpreting the Data Reader’s Display
Data Reader Display
firealarmresources.com
