Home made Discharger
 

I was wondering if it was possible to utilise my orion stick pack discharge board in series to make use of the fact it cuts out at 5.4volts. That way I can wire in a couple of fans- to not only drain my packs but cool them whilst doing so- does that make sense.
Not being a sparky- how could this be done? I thought that if the fans/ and or discharge bulbs were before the discharge board this would work. Am I right?
Hope this thread makes sense- My mrs is sitting next to me absolutely caining me for my geekishness-She didnt know the answer!!!

:cry:

I believe it knocks the discharge off per cell, not as a pack, so no cell goes below 0.9v.

Individual cells?
 

The pack originally came with tamiya style plug- so i would have thought that it would take all cells down- how i dont know -to the 5.4volts.

I know that i could just but a charger/ discharger to do it- but i am tight and have already bought a charger!

ah right, I thought it was a discharge tray, my fault, it would be hard to do what you wanted, as the current would have to pass though it, the only way you really could do it is with a relay, but that gets complicated.

Thanks
 

Guess I'll have to stop being tight!

If you wire the fan in series, there will be a slight voltage drop across the fan because of the resistance of the motor, this will mean the discharger will cut off too early. The fan will also restrict the current flow.

If you wire them in parallel, then you should be ok. There will be a very slight voltage drop because of the increased current draw, but this will be minuscule. I can't see any problems with doing that. If you need a piccie, let me know and I'll draw something up.

Diagram as requested. Components in parallel (as shown in diagram) all receive the same voltage as each other so the cut off will be at the same point. Compare that with series where each component has the same current through them, but the voltage they "see" depends on their resistance (according to Ohm's law) and the total resistance in the circuit.

If you are still concerned, discharge without a fan and measure the pack voltage then repeat with the fan and see if there is a significant difference.

Many thanks
 

Cheers- soldering iron out tomorrow