GE iVent 201 Series User's Reference Manual page 46

Icon
CAUTION If the screen flashes "EXT" in red, the external battery voltage is low.
Replace the battery at once.
available
If the external battery connector is removed from the iVent
DISCONNECTED FOR 40 SECONDS before plugging it back in.
NOTE The iVent
external battery voltage drops below 10 volts, in order to prevent
damage to the external battery. Some batteries may pose a fire hazard if
discharged below specified minimum charge levels. Because the
ventilator draws variable current while it is operational, the voltages
Figure 6: On-Screen Power Status Indicator
Icon Name Power State
Power
When the iVent
power supply, the screen shows a 3-pronged
power outlet icon.
Power
When disconnected from the AC power supply,
disconnect
the 3-pronged outlet icon is displayed with a red
"X" throughout.
DC power
When connected to an external DC power supply
connected
such as a battery, the screen shows "EXT" in blue
and AC
power
connected.
No External
When disconnected from the DC power supply,
battery
the screen shows "No EXT" in black
connected
201 is designed to switch off the external DC battery if the
TM
34
201 is connected to an AC
TM
Ensure adequate power is immediately
TM
201 IT MUST REMAIN