WalkAbout Hammerhead 3 User Manual - page 20
Chapter 3 – Software Operation
WalkAbout Computers HAMMERHEAD 3 User’s Guide – v021101
39
EDV1
Shows End Discharge Voltage, which is the voltage at
which the unit stops using the battery. The voltage
must drop below this value as part of the calibration
cycle.
TTE:
Time to empty, an estimate of the time to discharge
this battery.
TTF:
Time to full, an estimate of the time to fully charge this
battery.
Before calibrating your batteries, make sure your computer is hooked
up to an AC Power supply. You are now ready to press the Calibrate
button at the bottom of the screen. You should only perform this
function at a time when the unit is expected to be idle. This cycle must
be performed without interruption and may take over 4 hours for each
battery. During calibration, the batteries will be fully charged followed
by a full discharge and then fully charged again. Do not change or
remove batteries during this process. The battery calibration cycle will
continue until competed but can be cancelled at any time should it be
necessary to use the system.
Chapter 3 – Software Operation
WalkAbout Computers HAMMERHEAD 3 User’s Guide – v021101
40
Special Instructions for Cold Weather Operation
If your computer is equipped with an
optional
heater for cold
environments, you can change the settings by going to the HHUtility,
Properties Tab and checking the buttons as shown below. The heaters
will
only
operate when the power is supplied from a stable AC source,
irrespective of the preset settings.
Standby: (Activates heater while computer is off)
Check this box if you want the heater to operate even
when the machine is turned off.
If this option is checked, the LCD and Hard drive heaters will
turn on each time the temperature falls below 32
o
F and the
computer is turned off. The heaters will be activated long
enough to bring the unit to 40
o
F. Maintaining the unit at 32
o
F
will avoid the pre-heat delay when booting in a cold
environment but can drain even a car battery if left on for long
periods (such as over the weekend).
CAUTION
: The standby heaters will cause a current draw of
1.8A (@ 15v)) when operating. The cycle period will depend
on the ambient temperature to maintain the unit above 32
o
F.
An additional 1.0A will draw if the batteries are also charging.
This can severely deplete a car battery if it is the source of
external power.
Pre: (Activates heater while computer is booting)
Check this box if you want the heater to operate when
the machine is first turned on.
If this option is checked, the LCD and Hard drive heaters will
turn on when you boot your machine if the temperature is
below 32
o
F. The heaters will operate for a time to bring the
unit up to 32
o
F before the main system is activated. During
this time, the LED display will blink in an alternating “police”