User manual

2004 Stevens Water Monitoring Systems Inc. All Rights Reserved.
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2.7.3 Using a COM port for Charging
It is also possible to trickle charge The Shark’s internal battery using the serial or COM
port on your PC or laptop. This works best when the unit is turned off (switch 1 in the
“OFF” position) and The Shark is not in use.
You must be plugged into a PC or laptop computer’s COM port using a null modem
serial cable or adapter. The null modem adapter is not included with The Shark package,
but is provided by Stevens as an optional item. The COM port must also be active
(connected) in order for trickle charging to happen.
This charging method supplies about 10mA of charging current to the battery. It will
ONLY work if there is no external power source applied, The Shark is turned off, and the
COM port is active. If The Shark’s power is turned on, charging will take longer due to
the illuminated red LED and the current draw from the internal electronics.