Guralp Systems CMG-DM24 - Manual (Page 12)

Operator’s Guide DM-24 Digitiser
Issue G January 2003 10
Data:- 10 pin Mil-Spec plug for digitiser power, receive and transmit digital data
GPS:- 10pi Mil-Spec plug. Carries power supply to the GPS, receive and transmit data,
and 1 pulse per second reference signal.
Auxiliary:- Optional eight 16 bit, 4 samples per second channels primarily for ‘state of
health’ monitoring, e.g. sensor mass position, external temperature, pressure,
battery voltage.
POWER SUPPLY REQUIREMENTS
The CMG-DM24 unit operates from a wide input voltage range of 10 to 36 Volts DC.
The power consumption for the portable surface unit is:
CMG-DM24 - 3 Channel -115mA from 12 Volts
CMG-DM24 - 6 Channel -145mA from 12 Volts
CMG-GPS1-190mA from 12 Volts
CMG-GPS2-75mA from 12 Volts
The given power supply current requirements are a guideline. There are many factors
which can influence the power consumption of the sensor system, for this reason it is
recommended that the user should budget more generously when choosing power
supplies than the given typical values.
The listed power supply consumptions should be checked against the supply
requirements given in the calibration documents.
A dc-dc converter is used within each module of the system (sometimes
more than one dc-dc converter is used within a module) and it is
generally recognised that the start up current of such dc-dc converters
can be a factor of 5 to 8 times larger than the quiescent currents given
above.
NOTE