Simtronics GD1 MK3, Operating Manual

Page: 46 / 76

GD1 Page 46 of 76 850-816926-EN R06
6.2. Tuning detector for less noise
It is normal to see fluctuations of the H
2
S signal below ± 8 ppm*m. This is due to noise in
the measurement. Several effects can influence the noise in the H
2
S measurement such as:
Alignment between RX and TX, dirt on lenses, rain, sandstorm, snow, reflections and
interference from other detectors. The interference from another detector will typically be
observed as sudden high values of H
2
S, and is described in section 6.3.
To tune for less noise on the GD1 the alignment can be adjusted slightly, as described in
the procedure below:
# Step description Illustration
1
Clean the lenses of both transmitter (TX) and
receiver (RX) for any dirt before proceeding.
The optical path should be clear at the time of
aligning (avoid fog, mist, steam, rain, snow,
etc.).
2
Log into the service interface with Ethernet
connection or HART®.
3
Observe H
2
S level and signal strength on the
Web Interface Status screen, or with a mA-
meter on terminal 7 (H
2
S signal) and 8 (signal
strength). It is normal for the H
2
S signal to
fluctuate up to ± 8 ppm*m.