HOBO U30 Station (NRC) User’s Guide
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Maintaining the Battery
The rechargeable battery requires an external power source to work properly.
The Power section on page 63 explains this in detail as well as how to
maximize battery life and how you can expect the HOBO U30 Station to
operate at varying voltage levels.
If you are using a solar panel for recharging the battery and there has been a
steady decline in battery voltage, you will need to make a change by either
reducing power consumption or increasing recharging current. Start by
reducing the logging interval and/or excitation current (if you are using it).
Try cleaning the solar panel or repositioning it for maximum sunlight. You
can also attempt to recharge the battery for 24 hours.
If the voltage is still low after attempting to recharge the battery with an AC
adapter for 24 hours, then you may need to charge it with a current limited
variable power supply or replace it (both tasks are described below)
Important
:
Due to the self-discharge characteristics of this type of
battery, it is imperative that you charge the battery for at
least 12 hours every six months at minimum, even if you
are not actively using the HOBO U30 Station. Otherwise,
permanent loss of battery capacity may occur.
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HOBO U30 Station (NRC) User’s Guide
Charging a Dead Battery
In the event the battery is completely dead (less than 3.0 volts and the logger
lights do not come on when the battery is connected), you can charge the
battery externally with a current limited variable power supply (otherwise
you must replace the battery). Hold the battery across a constant voltage
source of 4.5 volts with a current limit of 2 Amps. When held at this voltage,
the battery will seek its own current level and maintain itself in a fully
charged condition. It takes up to 24 hours to fully charge a dead battery.
Important
:
Do not apply more than 4.6 volts absolute maximum to the
battery. Do not exceed 2 Amps of current when charging.
If the battery gets hot, immediately stop charging the
battery. If the battery will not hold charge, it must be
replaced. Dispose of the old battery per local regulations.
