Servomex 07931001B, Operator'S Manual

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© Servomex Group Limited. 2020 07931001B revision 6
To open the cover, slide the latch to the left.
Insert the micro SD card into the slots in the cover.
Close the cover and push the latch to the right to secure it.
The SD card connector is used for:
•
Data logging
•
Software updates
•
Settings (save / restore)
The current log will be exported to the selected log media.
5.4 Saturation
There are three distinct types of saturation that can occur with the Laser 3 plus
analyzer.
Photodiode DC level Saturation
This type of saturation is where too much laser energy gets to the detector. When
the detector is saturated in this way, the measurement cannot be relied upon as the
photodiode DC level can no longer respond accurately to increasing laser energy.
In this situation, the analyzer will return an (X) on the display (E flag) and status
history will show ‘C29I00 SATURATION’ and ‘C35I00 STOPPED’
. In order to
avoid/stop this error appearing commissioning the analyzer should commence with
lower DC1 or DC2 gains, and then consequently increase to reach recommended
Photodiode DC level (below 1.5V for O2 and below 2V for NH3, CO, CO+CH4).
Reference the note in section 4.11.1 regarding maximum photodiode DC levels.
Optical depth Saturation
Optical depth saturation occurs when there is too much absorbing gas which
reduces the amount of laser energy reaching the photodiode at absorption line
wavelengths to near zero. In this case, the sample becomes opaque at the
absorption line wavelength and the analyzer will not respond to increasing amounts
of absorbing gas and will instead report last correctly measured concentration with
an (X) on the display (E flag) and status history will show ‘C29I00 SATURATION’
and ‘C35I00 STOPPED’.
.
When an absorbing gas reaches a certain optical depth (defined in terms of %.m or
ppm.m), the relationship between increasing concentration and increasing