Solar Panels; Direct Battery Connection To The Cr510 Terminal Strip; Vehicle Power Supply Connections; Connecting To Vehicle Power Supply - Campbell CR510 Operator's Manual

PS12LA. A common use for the PS512M is in
radiotelemetry networks. The PS12LA cannot
be modified to a PS512M.
The maximum current drain on the 5 volt supply
of the PS512M is 150 milliamps.

14.4 SOLAR PANELS

Auxiliary photovoltaic power sources may be
used to maintain charge on lead acid batteries.
When selecting a solar panel, a rule-of-thumb is
that on a stormy overcast day the panel should
provide enough charge to meet the system
current drain (assume 10% of average annual
global radiation, kW/m
information, if available, could strongly influence
the solar panel selection. For example, local
effects such as mountain shadows, fog from
valley inversion, snow, ice, leaves, birds, etc.
shading the panel should be considered.
Guidelines are available from the Solarex
Corporation for solar panel selection called
"DESIGN AIDS FOR SMALL PV POWER
SYSTEMS". It provides a method for
calculating solar panel size based on general
site location and system power requirements.
If you need help in determining your system
power requirements contact Campbell
Scientific's Marketing Department.
CR510
2
). Specific site
FIGURE 14.6-1. Connecting to Vehicle Power Supply
SECTION 14. INSTALLATION AND MAINTENANCE
14.5 DIRECT BATTERY CONNECTION
TO THE CR510 TERMINAL STRIP
For some applications, size restrictions or other
operational considerations may preclude the use
of Campbell Scientific power supply options. In
these cases the power supply may be connected
directly to the terminal strip. Any 9.6 to 18 VDC
supply may be connected to the 12 V and G
terminals on the terminal strip. The metal
surfaces of the terminal strip and mounting
bracket are at power ground. Make connections
to the terminal strip first and then to the power
supply. If the power supply must be connected
first, connect the positive to the terminal strip
before the ground to avoid shorting to the
terminal strip or mounting bracket.
14.6 VEHICLE POWER SUPPLY
CONNECTIONS
If a CR510 is to be powered from the 12 Volts
of a motor vehicle, a second 12 V supply is also
required at the time of vehicle start-up. When
the starting motor of a vehicle with a 12 V
electrical system is engaged, the voltage drops
considerably below the nominal 12 V, which
would cause the CR510 to malfunction every
time the vehicle is started. The second 12 V
supply prevents this malfunction. Figure 14.6-1
shows the general case for connecting the two
supplies to the Terminal Strip. The diode allows
the vehicle to power the CR510 without the
second supply attempting to power the vehicle.
To reduce the potential for ground reference
errors in measurements, the ground lead should
be 16 AWG or larger.
14-5