Guralp Systems CMG-DCM build <10,000 User Manual
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Acquisition Modules and Platinum Firmware
Digitiser Configuration
The periods over which the short term and long term averages are computed,
along with the triggering ratio itself, can be altered by changing values in the
table. The check-boxes next to each component are used to enable or disable
the use of that component's output in the STA/LTA triggering algorithm.
The tap to be used as input should be selected from the Trigger input
drop-down menu. All configured taps are available, regardless of whether
they have been selected for continuous output or not.
The check-boxes labelled with component designators are used to include or
exclude the associated component from the triggering algorithm. If one is
ticked, a trigger will be activated if that component's instantaneous output
exceeds the value entered into the Triggering level field in the same row.
Full coverage of external triggering is beyond the scope of this manual and the
interested reader is referred to the relevant digitiser manual.
The pre-trigger time and post-trigger time drop-down menus control the
amount of data transmitted around each trigger period. The options offered
range from 5 seconds to 4 minutes. The “0 seconds” setting disables the
feature.
The
button inserts and extra row in the decimator output
table and returns the display to the main digitiser configuration settings
screen.
8.1.1.8 Multiplexor channels
The next section of the main display shows and controls the transmission of
data from the auxiliary and state-of-health channels of the digitiser:
Inputs M3 through M7 and MB through MF are typically derived by digitising
(at 16-bit resolution) the analogue inputs on the “Auxiliary” connector of the
digitiser although, in some configurations, they may be connected to internal
sensors. For example, ME is often used for an internal temperature sensor
and M8, M9 and MA provide mass position data from the first sensor. Output
from each displayed channel can be enabled by ticking the associated
check-box or disabled by clearing it.
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Issue E - February 2014