For those of you who have a collection of batteries and battery packs !
Testing battery packs has become a daily activity lately, and having some way to drain large capacity "AH" ( Amp / Hour ) battery packs in the comforts of home has become a need...
One option, strap a pack to a bike and go for a ride!
However, this is not always practicle or possible when troubleshooting battery " Pack " problems.
Parts Needed: ( any hardware store )
3 x Double lightbulb ceiling fixtures = 2$ each
Scrap piece of 2 x 4 = Free
200w, 120v G.E. Lightbulb = 2$ each
Anderson Powerpoles = 1 $
Total : 19 $
For under 20 $ you have a device that wil drain a 72v battery pack at 600w . If you go online and search for various RC ( Remote Control ) battery testers, they cost from 10 to 600 $ with all kinds of fancy USB graph capabilities etc..
Those are great, but if you are on a budget and/or do not need 100 % accurate performance data, this is pretty close and an easy way to do it.
As shown above, I connected all positive(white) and all negative(black) leads together, you can add as many fixtures as you like, more of them means you can add more bulbs and burn more energy.
I use anderson Powerpoles
Video on how to crimp powerpoles :
Once you start to gather different battery packs and more charagers, having every connector the same makes life much easier. Some people prefer " Deans " connectors, but personally I prefer Andersons. There are all sorts of other options available, but i highly recommend andersons.
On The Left- 15/30 Amp ..... On The Right- 45 Amp
Better Tool :
Below are just a few examples of how i use andersons on everything..
So, why household lightbulbs work ?..
Incandescent bulbs come with a " Watt " rating.. typically 40w to 100w ..
And they are made to run on 120v, they will consume the rated watts at 120v, however, with lower voltage they will consume less power, so at 60v you can expect roughly half the rated watts.
The higher watt bulbs have less resistance and allow more energy to flow thru them in the process shine brighter..
As long as the battery being used has less voltage than 120v, the bulbs will not blow.
Do not make the mistake of using automotive bulbs rated at 12v, those will blow as soon as you go over 14v or so.. However if you want to drain a single cell or a few cells below or at 12v, they can also work fine !
For the complicated answer, see: Ohm's Law !
Lower voltage will result in less light, more voltage = brighter = more amps
There you have it, a cheap way to exercise your battery pack !