Campbell Scientific SP50-L/SP90-L Solar Panel - Manual (Page 24)

SP50-L/SP90-L Solar Panel
For help in troubleshooting the solar panels, please contact a Campbell
Scientific applications engineer.
5. Power Considerations
5.1 Proper Solar Power and Lead Acid Battery Sizes
The solar panel converts light energy to electricity, or specifically to direct
current. The direct current produced is used to provide power to the system
and to charge lead acid batteries.
The solar panel operates in both direct and diffuse light (cloudy days), but not
at night.
The minimum battery size and solar panel output required depend on 1) the
average current drain of the system, 2) the maximum time the battery must
supply power to the system without being charged, and 3) the location of the
site.
When some batteries are discharged below a specified voltage,
the battery becomes damaged and cannot be recharged. NOTE
On the average, the solar panel must be able to provide at least the amount of
power necessary to operate the system for 24 hours. This means that the solar
panels should not only be able to supply power to the system during the day,
but it should also be able to provide power necessary to charge the battery for
the power lost during the night. In addition, the battery must have enough
capacity to power the system during times of no charging (night) and several
days of low charging (cloudy and stormy days). For additional help in
computing power budget for a specific system, please contact a Campbell
Scientific applications engineer.
5.2 Voltage Regulator
The regulator has two basic functions: 1) blocking any current flow from the
battery to the solar panel, and 2) limiting the source current to the battery.
The CH200 is a microcontroller-based smart charge controller that is ideal for
external rechargeable 12 Vdc VRLA (Valve Regulated Lead-Acid) batteries
like the BP12 or BP24. The controller manages amperage and voltage for safe,
optimized battery charging from a solar panel or AC power sources. It also
measures various input, output, and status parameters to allow close monitoring
of the battery.
The Morningstar SunSaver™ SS-10-12V regulator can also be purchased from
Campbell Scientific, and it is not shipped with a solar panel. The regulator
connects to the battery via the 15’ long 16AWG cable shipped with the
regulator.
The regulator and battery should be housed in an environmental enclosure.
Mounting brackets are included with the regulator for attachment to an
enclosure backplate.
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