rtd UPS25, Руководство пользователя

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UPS25 22
RTD Embedded Technologies, Inc
Ni-Mh/Ni-Cd battery charger
Ni-Mh/Ni-CD Battery Pack and Thermistor
Battery packs using Ni-Mh/Ni-CD technology are the only ones supported by the
standard UPS25. RTD Embedded Systems, Inc. can deliver UPS25 units that
support Ni-Cd technology. An UPS25 that is configured for Ni-MH batteries may
not be used with Ni-Cd and vice-versa. For the UPS25 to operate correctly a total
of 8 AA-cells must be used connected in series. This connection will give a
nominal output voltage of 9,6V over the battery pack. In real life the battery pack
voltage will range from
11V fully charged to 6,5V absolutely discharged. The battery pack must contain
attached to it an NTC temperature sensor called a thermistor. The output of the
thermistor is monitored at periodic intervals by the charger circuitry. If no
thermistor is detected, the charger will not charge the battery. Not just any
kind of thermistor can be used, since many component values are trimmed to
meet the characteristics of the thermistor. If an incorrect thermistor type is used
the charger circuitry of the UPS25 may not work properly. Below is listed the part
number and specification of the recommended thermistor:
Part number:
SIEMENS B576164K103J
Resistance at +25C 10 K, +-5%
Beta value +25C to 100C 4300, +-3%
These parts can be ordered through RTD is case you wish to construct your own
battery pack to use with the UPS25. For custom dimensioning of the charger to
support another thermistor, please contact our technical support for assistance
and formulas for component value calculation.
The UPS25 is dimensioned to charge a battery pack with a maximum capacity of
1500mAh. The charging algorithm is set to a nominal charge current of 750mA i.e.
C/2. This setting is used to determine the fast charge and top-off charge times of
the charge process.