Yuasa NP Series, Руководство пользователя

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Solar Powered Chargers
A battery is an indispensable component of any solar
powered system designed for demand energy use. Since
solar cells have inherent constant voltage characteristics,
NP batteries can be charged directly from the solar array
using a simple diode regulated circuit as shown in Figure
24.
In designing a solar powered system, consideration
should be given to the fact that in addition to normal
periods of darkness, weather conditions may be such
that solar energy is limited, or virtually unavailable for
long periods of time. In extreme cases, a system may
have to operate for 10 to 20 days with little or no power
available for charging. Therefore, when selecting the
correct battery for a solar application, the capacity should
be determined based upon maximum load conditions for
the maximum period of time the system may be expected
to be without adequate solar input.
In many instances the battery capacity will be 10 to 50
times greater than the maximum output of the solar
panels. Under these circumstances, the maximum output
of the solar array should be dedicated to charging the
battery with no load sharing or intervening control devices
of any kind.
Naturally, in cases where the output of the solar array
exceeds the capacity of the battery, and weather
conditions are such that the potential for overcharging
the battery exists, appropriate regulated charging circuitry
between the solar panels and the battery is recommended.
Remote sites and other outdoor applications is where
most solar powered systems are to be normally found.
When designing a solar powered system for this class of
application, a great deal of consideration must be given
to environmental conditions. For example, enclosures
which may be used to house batteries and other
equipment may be subject to extremely high internal
temperatures when exposed to direct sunlight. Under
such conditions, insulating the enclosure and/or treating
the surface of the enclosure with a highly reflective, heat
resistive material is highly recommended.
In general, when designing a solar powered system,
consultation with the manufacturers of both the solar
panel and the battery is strongly advised.