Guralp Systems CMG-3ESPCD User Manual
Page 13
CMG-3ESPCD Digital Broadband Seismometer
Installing the 3ESPCD
6. Plug the grey/blue power/data cable into the ten-pin connector on the
instrument's lid and connect a 12 V power supply to the ends of the
grey cable. Connect the DE9 connector to a PC running scream, using a
USB-to-RS232 converter, if required.
Note: GSL strongly recommend USB/RS232 convertors
based on the FTDI chipset. Numerous problems have been
found with convertors based on the other common chip-set.
Alternatively, connect the ten-pin connector on the instrument's lid to a
CMG-EAM using cable CAS-DCM-0001 (green).
7. Plug in the GPS cable and connect the GPS receiver.
8. In Scream's set-up dialogue, select the “COM Ports” tab and set the
Baud rate of the appropriate COM port to 38,400 Baud. Click OK and
wait for the instrument to appear in Scream's source tree.
Right-click on the digitiser's entry in the source tree and select
Control.... Click on the Mass control tab, followed by Unlock. (If the
Mass control tab is unavailable, check the sensor type in the Sensor
type tab, apply, and open a new Control window.)
Alternatively, if you are using an EAM, navigate to the Control →
Instruments Port X Instrument... page and click on the Unlock
→
instrument button.
Caution: After this point, you should be careful not to tilt
the instrument or you may damage it.
9. Right-click on the digitiser's entry in Scream's source tree and select
Control.... Click on the Mass control tab, followed by Centre.
Alternatively, if you are using an EAM, navigate to the Control →
Instruments Port X Instrument... page and click on the centre button.
→
Monitor the mass positions during the centring operation. You may
need to initiate several rounds of centring before the mass positions
reach an acceptable value.
10. Cover the instrument with thermal insulation, for example, a 5 cm
expanded polystyrene box. This will shield it from thermal
fluctuations and convection currents in the vault. It also helps to
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Issue B - November 2013