Campbell CH201, Product Manual

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1. Introduction
The CH201 is a charging regulator for an external rechargeable 12V VRLA, valve-regulated lead-
acid, battery, such as the BP12 or BP24 offered by Campbell Scientific. Charging power for this
charging regulator is typically supplied by an unregulated solar panel or AC-to-DC converter.
The CH201 is a smart charger that provides a programmable low voltage disconnect and two-step
constant voltage charging with temperature compensation for optimal charging and battery life.
A maximum power point tracking algorithm is incorporated for solar inputs to maximize available
solar charging resources.
The CH201 is a series regulator, which has the regulator placed, in series, between the charging
source and the load. As batteries become closer to fully charged, series regulators reduce the
current drawn from the charging source. The charging source may be completely unloaded if full
charge is reached. Charging source unloading is acceptable for solar panels and AC-to-DC
converters. For wind turbines, charging source unloading can cause free spinning. Consequently,
do not use series charging regulators, such as the CH201, to regulate wind-turbine outputs
without a method to load the turbine when the batteries require little or no charging current.
The CH201 has several safety features that protect the charging source, battery, charger, and load
devices. Both the DC In 1 and DC In 2 input terminals have polarity reversal protection and
programmable hardware current limits. The CH201 has a programmable maximum battery
charging current limit. A self-resettable, thermal fuse is in-series with the 12 VDC output
terminals to protect the charger from an output load fault. The CH201 includes battery reversal
protection, and ESD and surge protection are incorporated on all inputs and outputs.
2. Precautions
Only use the following battery cables with the CH201: pn
#
34029, pn
#
34031, pn
#
34040,
and pn
#
36589.
Overcharging VRLA batteries can produce excess hydrogen and oxygen gases, and the
accumulation of hydrogen gas can form an explosive mixture. Fortunately, hydrogen gas is
difficult to contain in anything but a metal or glass enclosure.
CH201 12V Charging Regulator 1