Guralp Systems CMG-3ESPCD User Manual
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CMG-3ESPCD Digital Broadband Seismometer
Using Scream!
The two boxes at bottom right of the Triggering pane allow the user to set the
pre-trigger and post-trigger data intervals, in seconds. These values determine
the minimum length of time during which data will be saved before the
trigger condition occurs, and after it has lapsed. Regardless of the intervals
chosen, the data in the triggered streams will begin on a whole second.
5.1.4 Mux Channels
The digitiser provides a range of slow-rate auxiliary channels for reporting the
system's state of health and other diagnostic information, known as
multiplexed (“Mux”) channels. In the 3ESPCD configuration, three of these
are used to report the sensor mass position and another is used for measuring
the internal temperature of the digitiser.
The collection and transmission of these environmental channels is
controlled using the Mux Channels pane:
If a tick is placed in the box next to a channel, its data will be collected and
transmitted as a data stream in GCF format, just as with the normal data
channels. To indicate that the data comes from a Mux channel, the Stream ID
will take the form ****Mx, where M stands for Mux and x is a hexadecimal
integer (i.e. 0 – 9, and A – F for 10 through 15). Z, N/S and E/W Mass Position
Mux channels appear as M8, M9 and MA respectively. The digitiser also
monitors its internal temperature, which is reported on channel ME.
5.1.5 Ports
The Baud Rates pane of the Configuration set-up window allows you to
program the baud rate and stop bits for the digitiser's output port.
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Issue B - November 2013