I learned that trick charging ni-cads on my RC airplane. How to
have the batteries ready when I fly only 1 mourning a week.
This keeps the battery from over charging or 'burning out' also.

I have my emergency power for 12v and jumper cable power box this way.
I my 11" telescope power pack for the RV wheel set this way.

Works.
Martin

On 10/20/2014 2:43 AM, Lew Hodgett wrote:
The major drawbacks to the Harbor Freight cordless drill is the
recharge time (3-5 hours) and there is no indication that the
battery is finished recharging.

Below is an automatic shut off circuit using standard shelf
componets.

Enjoy.

Lew
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Hardwa

1, 6 circuit switched power outlet strip.
1, Manual 24 hour timer with two switched outlets.
2, LED night lights.

Directions:

Program the timer to be "ON" for 5 hours and
"OFF" for 19 hours.

I used "ON" at 00:00 (midnight) and "OFF" at 5:00 AM.

Plug timer into power outlet strip.

Plug an LED night light into power outlet strip.

Plug an LED night light into 24 hour timer outlet.

Plug the 24 VDC "WallWart" from the Harbor Freight
recharger module into a 24 hour timer outlet.

Plug 24 VDC plug from the "WallWart" into the
Harbor Freight recharger module and insert battery
to be recharged.

Plug power outlet strip into a source of power.

Rotate timer cam until it just touches the "ON" cam.

Turn the power outlet strip "ON".

The LED night light plugged into power outlet strip
should turn "ON".

When the cam turns "ON", the LED night light
plugged into a timer outlet will turn "ON" and the
RED and GREEN lights on the battery charger
will turn "ON".

After 5 hours, the timer will turn "OFF", the
LED night light plugged into timer outlet will
turn "OFF" and the RED and GREEN lights on
the battery charger will turn "OFF".

At this point, turn the power outlet strip "OFF".

The LED night light plugged into power outlet strip
should turn "OFF".

Remove the battery and allow to cool.

NOTES:

The timer only allows the recharger to be on for
5 hours and then turns "OFF" for 19 hours.

It will recycle if you haven't if you haven't turned
off the power during that 19 hour period.