Axetris AG
LGD Compact Integration Guide V1.8
04.12.2019
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2.7 Gas supply
The piping system surrounding the sensor is important. Leaks in the piping system can falsify the results. It
is therefore recommended to carefully check the system for leaks. The use of correct fittings and sealing
helps to avoid leaks. Use standard pressure reduction equipment on gas bottles. Maximum standard flow
is 2 l/min. The minimum should be 1 l/min in most applications.
When no gas tubes are connected to the sensor module or the sensor is on stock the gas
connector plugs
should be used to prevent the gas cell from contamination.
When measuring potentially dangerous concentrations of toxic gases (CH4
,
C2H2, etc.),
properly vent the exhaust of the sensor to a safe area. Improper venting of the exhaust may
cause serious personal injury.
2.8 Adjusting firmware integration time (T90)
Depending on the application the sensor sends one or two values per second. The integration time can be
increased for applications where longer measurement periods can be accepted. This reduces the noise of
the measurement but increases the reaction time when changing the gas concentration. If the integration
time is increased, the measurement values sent by the sensor represent a moving average. The type of
averaging used is an exponential weighted average (1-pole
IIR filter
similar to an RC filter, for further
information check LGD FAQ document).
It is characterized by the time necessary to reach 90 percent of the
final value (T90). The character of this type of integration is very similar to a standard moving average, but
is more economic in terms of memory take-up. The value set in the user interface will be saved in the
firmware of the sensor and thus is available even after disconnecting the sensor from the PC and when the
analog output is used.
Min value:
0 s (no Integration)
Max value:
600 s (limited to this value)
The integration on the concentration values is directly linked with the analog output. The
measured concentration is directly transferred into an analog value.
The values for integration time can be set in the Customer Frontend in the menu "Settings" -
> "Sensor Parameter", changed parameter can be saved in EEPROM with "OK" button.
3 INSTRUCTIONS FOR LGD SYSTEM INTEGRATION
Please also check for relevant information in Chapter 2 regarding system setup for
evaluation.
3.1 Integration options
In order to facilitate the integration of the LGD Compact-A module into a customer-specific device or
instrument, the electronics housing as well as the interface board can be removed and the module can be
operated with the main board only. In this case, an appropriate shielding aiming to avoid signal interferences
as well as the EMC conformity has to be fulfilled by the integrating Original Equipment Manufacturer itself.
Important: the EMC conformity will only be granted for product executions delivered with electronics
housing AND after official product launch.
When integrating the LGD Compact-A without electronics housing and without the interface board, the
integrating Original Equipment Manufacturer has to ensure an appropriate shielding, in order to avoid signal
