4
3. GENERAL OPERATION
The Xtrema's menu system was designed to be simple and intuitive. When you first connect the Xtrema
to the input power it will display the welcome screen for a few seconds before going to the main menu.
The welcome screen will display the firmware and hardware revision numbers which should correspond
to this manual.
When in the main menu a blinking square box is used to draw your attention to the current selection or
the choice that is to be made. All operation is via a single joystick that can be slightly moved in four
directions. In all cases operation is simple as noted below.
Up
or down
buttons on the joystick select menu or value options Left
goes back to previous selection, right
button accepts option and goes to next step
Note:
Pressing
the joystick button to the Left
while in the Main Menu will force the
Xtrema to shut off the display and go into a standby / off state. Momentarily pressing the joystick
again in any direction will restart the Xtrema back to normal operation
4. CHARGING a Lithium (Li) Battery
Overview - How the charger works
The Xtrema charges lithium batteries using the constant current to constant voltage method
(CC/CV) recommended by Lithium battery manufacturers. When you start a charge cycle, the
first thing the Xtrema does is test to see if the pack voltage is plausible for the cell count and
volts per cell you have selected. It does this during the
TESTING
phase
If all is OK, the Xtrema proceeds to increase the battery voltage just enough to maintain the
charge current you selected. This is called the constant current phase and is indicated with
"
Charge CC
" on the display. This constant current phase continues until the voltage eventually
climbs to the end value. (Volts per cell X cell count)
At that point the Xtrema enters the constant voltage phase indicated by "
Charge CV
" on the
Joystick
To Motor Under
Test
To Battery
Temperature
probe connector
Expansion
port
LCD
Display
POWER INPUT
(10.5
–
15 volts DC)
Fan
(on side)