Campbell CH150, Product Manual

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User Manual
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An AC/DC converter charge source could be connected to either the CHARGE –
CHARGE input terminals or the SOLAR - G
input terminals. The best input
terminals to use with a given AC/DC converter should be based on the converters
output current capability. For example, the CHARGE – CHARGE input terminals
provide a current limit of 1.1 Adc on the charging source. Whereas the SOLAR -
G
input terminals have a fixed 3.6 Adc typical current limit, providing faster
battery charging for a charge source that can deliver up to 3.6 Adc current without
damage.
The SOLAR – G terminals are optimal for solar panels because of the high-current
charging capability when solar resources are available. A Maximum Power Point
Tracking algorithm is also utilized when the PS150/CH150 detects the charging
source is connected to the SOLAR input.
The +12 V output terminals are intended to power a datalogger and any
peripherals. Power to these output terminals is controlled by a toggle switch, with
the total output current limited by a 4.65 A solid-state circuit breaker (see
Section 4.1,
Specifications ). The A105 Additional 12 V Terminals Adapter may
be used to provide extra 12 V and ground terminals where the power supply is
used to power several devices, noting that the hold current limit on the 4.65 A
solid-state circuit breaker still applies (see
Section 8 , A105 Additional 12 V
Terminals Adapter ).
6. Charging Details
6.1 Charging Algorithm
The PS150/CH150 offers both Continuous and Solar charging inputs. The
Continuous charging input has a maximum value of 1.1 A DC to help protect
AC/AC transformers and AC/DC converters. The 3.6 ADC typical current limit
of the PS150/CH150 Solar charging input is well suited for 70 W solar panels.
Typical Continuous charging inputs would be AC/AC transformers or AC/DC
converters in which a charge voltage is continuously applied except for line power
outages.
The PS150/CH150 uses a float charging algorithm for either the Continuous or
Solar charging inputs. This charging method can charge a battery indefinitely
without overcharging a battery.
6.2 Maximum Power Point Tracking
The current and power versus voltage for a 70 W solar panel are illustrated in
Figure 6-1. As can be seen from the figure, a Maximum Power Point of operation
exists for solar panels. Adjusting the load on the solar panel so it operates at this
Maximum Power Point is referred to as Maximum Power Point Tracking (MPPT).
MPPT is beneficial when insufficient power is available from the charge source,
which is the case during current limited charging. The somewhat noisy charging
current and voltage during the initial current limited charging stage is due to the
MPPT algorithm of the PS150/CH150 searching for the maximum power point of
the associated solar panel.