Re: (ET) Stock E20 charger /reinventing / monitoring

[JBR <reinharj frontiernet net>]

As some pointed out - the OEM GE Ferroresonant charger is not terrible, 
just 
not as automatic as we might like, and not fail safe (and, it does not 
check 
the electrolyte level in any of the cells, for us <grin>).

My suggestion to use a microcontroller was intended as a step up from the 
Landis system:  
(1) Still fairly low cost (parts wise), 
(2) Still use OEM battery charger.  
(3) Add Voltage readout ($3 digital meter from Harbor Freight could do 
this 
part), 
(4)  Add Voltage related control - linked to charging (this requires SOME 
type 
of control circuit - from simple Zeners, to comparators, to microprocessor 
control, etc).  
(5) Add current monitoring (fairly easy, if you have already added a $5 
microprocessor to your design)
(6) add real time clock (again, easy if you already have microprocessor) 
to 
enable alerting 
(7) Add temperature sensor - boiling batteries warm up (easy for micro to 
shut 
down the system)!
(8) Add Electrolyte level sensors ? This could add up $$ - maybe more 
expensive than those special HYDRO-Caps ($7 each) that reduce water loss 
...  
(but not necessarily - maybe sensor that attaches to outside of battery ?)
(9) Log energy used to Charge (Kill-A-Watt for $23 on EBay does this) - 
again, 
not too hard if you already have the microprocessor, and current 
monitoring.
(10) Add piezo buzzer, flashing lights, other alert devices (pretty easy 
in 
any system)

Anyway, the point was that a small circuit board can cost under $5 in 
quantity,  and can include layout for a variety of options, and with open 
source software, a variety of people could contribute modules - SO, they 
hardware and software would be modular. ALSO, we could search the net - 
half 
or all of this might already have been done.

The Microprocessor costs between $1 and $6, then 5 volt regulator, 
crystal, 
misc resistors, capacitors & pushbutton switches total a few dollars, 
Colored 
LED's are 10-20 cents each, & an LCD might cost $10, etc. Total $20 > $25 
in 
parts, or so.

We - Electrak Owners - are not the only ones who might benefit:  My Comuta 
cars are also old, and have simple chargers, and a cheap, simple circuit 
change (and corresponding software change) would allow the above design to 
monitor its 48V pack, or 60 V pack, or my 12V Black & Decker Cordless 
mower, 
or my friends cheap Ryobi Drill charger, which bakes her batteries when 
she 
leaves the charger on too many days.  etc, etc, etc.

I was thinking along the lines of the old Heathkit Kits - since they also 
had 
a page in every manual which explained how they worked. 

Cost is also a concern - as I want the system built into the vehicle, and 
I 
own 3 Electraks, 2 Comuta cars, and a variety of other battery powered 
devices - SO, I don't want to buy fancy new chargers for all, when I could 
design (or hopefully find on the net) an economical charge 
monitor/controller 
[ NOT a charger ] and buy/build a dozen of them.




On Wednesday 08 August 2007 3:06:08 pm Jeremy Gagliardi com wrote:
> How many Amps output is the stock E20 charger?
>
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