GASSONIC OBSERVER-i
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of
≥
10 seconds should be set in the fire & gas system. For Enhanced Mode, an internal alarm delay
time
≥
2 seconds and an ANN Sensitivity Level between 54 and 84 dB is recommended. For maximum
coverage distance, the ANN Sensitivity Level can be set at 44 dB. The ANN Sensitivity Level is
indicated by “TL” in the menu structure (see Section 4.4.3).
Classic Mode
: The 4-20 mA represents 40 dB to 120 dB.
The output value in mA corresponding to the SPL in dB can be calculated by the following formula:
{[(n – 40) * 16] / 80} + 4 = x
n: Sound Level in dB
x: Output value in mA
Enhanced Mode
:
In Enhanced Mode, the unit utilizes ANN. This means that the unit is constantly calculating the
probability of the input being a real gas leak. In Enhanced Mode, the user has three Analog Outputs to
choose from. These outputs are:
Discrete SPL (EAO1 shown in display):
4 – 12 mA represents 40-120 dB. 16 mA for
Warning and 20 mA for Alarm (Warning is before the delay time runs out)
{[(n – 40) * 8] / 80} + 4 = x
n: Sound Level in dB
x: Output value in mA
Discrete (EAO2):
4 mA for Normal, 16 mA for Warning and 20 mA for Alarm
SPL Only (EAO3
): 4-20 mA represents 40-120 dB. This output mode is generally only used
with the GM HazardWatch or MSA Model 10k Fire and Gas Systems. The user can use the
SPL trigger to set the threshold for alarm, similar to that of Classic Mode. The SPL trigger
should be at least 6 dB higher than the background noise. The Alarm relay is controlled by an
adjustable trigger level in 5 dB steps, from 44 to 99.
