believe that Jeff sees support so we should see a response shortly. Can anyone other than Jeff give an
update on this? Any idea when CE
will be available. This will be a
certification issue. We must get
to a point where software is stable and not undergoing these constant changes
if we ever expect to have products
Larry J. Dix
firstname.lastname@example.org [mailto:email@example.com]On Behalf Of Ian S. Piper
Sent: Saturday, October 20, 2001 2:05
Battery Status & Charging
firstname.lastname@example.org [mailto:email@example.com]On Behalf Of Jeff Hintz
Sent: October 20, 2001 9:17
To: Support Team
County, KS - Battery Status & Charging
Johnson County, KS
has received 6 AVTS units for demonstration purposes. One of the units
says Low for the Battery Status instead of Charging, this unit has been
plugged in since they received it, over a week now. Does this mean
that the battery is bad, or that the indication of the battery does not
CE 2.12 has a bug where it always
reports the Main Backup Battery as a "Low" Status. This is apparently
corrected in Windows CE 3.0.
microcontroller is used to control battery charging/discharging and power
distribution. The PIC monitors the battery and reports a percentage of
the battery's charge capacity to WinCE, but at this time, the
BallotStation software doesn't use the Battery Charge Capacity
Percentage, only the status word (i.e., good, low, very low.) And WinCE
2.12 is stuck on "low". I don't know the outlook for implementing WinCE
3.0. Jeff Dean would be the person to make an inquiry to on that
They are in the
planning stages of their warehouse, and would like to know what our
recommendations are for charging of the AVTS units. Do the AVTS units
need to be plugged in continously???
don't need to be plugged in continuously. However, they can if they
wish. It won't harm the unit.
AVTS units need to be charged on a rotation
If it is
logistically more feasible for the warehouse staff to use a rotation schedule,
then they can do that. The battery charging circuit only needs AC
power attached to charge the battery. With the unit turned off and
AC applied, the system will be in slow charge mode and will only draw a small
amount of AC power (0.1A @ 110VAC). At that small of a current
consumption, quite a few units can be attached to a single
lead acid batteries lose approximately 3% of their charge per month just
sitting on the shelf. If left unused, they should be recharged a minimum
of once a year. Preferable would be once every six months.
Obviously, if they have more frequent elections cycles, and the units are
charged before and after each cycle, this minimum wouldn't be a concern.
But if they have spare units that are always held in reserve and never used,
then they should meet the minimum charging requirements.
Do the AVTS
units need to be charged only 24 hours before an
charge, a discharged battery will be charged in 12 hours. With AC
applied and the unit is turned on and operational, the charging circuit
switches into fast charge mode. This mode will bring
a discharged battery to 85% of full charge within 3 hours. This is
done by applying the manufacturer's maximum recommended charge current
into the battery. The system will switch to slow charge after reaching
the 85% point. Fast charging past that point can reduce the battery's
life expectancy. The purpose behind the fast charge mode is to maximum
charge time in a rolling blackout situation.
unit is using fast charge mode, it will consume more AC power ( 0.3A @
ballot station operation takes priority over the charging of the
battery. If the ballot station operation needs to draw power that nears
the capacity of the power supply (e.g, someone plugs in an unapproved PCMCIA
device that sucks the power down), then the battery charging circuit will
either reduce to slow charge mode or stop charging in favor of the ballot
station load requirements..
I will be going down
to Johnson County, KS on Tuesday for an all paper election, and they would
like to know the answers to these questions.
idle system will take 5-1/2 hours to discharge a fully charged battery.
This is with the LCD panel displaying constantly. If the software
is developed with a sleep mode for the LCD panel, this discharge time
could be considerably longer. The LCD panel and its backlighting draw
the most power.
tested configuration for the 5-1/2 hour discharge time used a 32MB flash
memory card as the only PCMCIA device. Other PCMCIA devices would draw
additional power and therefore shorten the discharge time. Printing
a paper tape on battery power draws considerable power, but that is cyclical
and not a concern for overall discharge time. Unless, of course, it is
discharge, when the monitored battery voltage reaches 10.5V, the system
will automatically shutdown. This is the 0% capacity point. Some
components in the system require a minimum of 10.2V for operation and the life
expectancy of a sealed lead acid battery will be reduced if it
is used below 10.5V. Life expectancy on sealed lead acid batteries
is 5 years.
that answers your questions on battery charging (and discharging).
Let me know if you need anything further.