Balance leads
 

Hey Everyone!

Hope you all had a wicked summer. :)

I have been using custom 22" charging leads that I made when I had my Hitec X4 80 which have only a single 22awg wire that runs to the balance pin on the battery. The other 2 22awg leads (pos + neg) run straight out of the balance plug and are soldered onto the pos and neg cables right at the charger side, so they are only about 3" long.

Now I'm running an iCharger DUO308 and it got me to thinking about the cables again and thought I'd post a topic here and see if its an issue?

It works with (what seems like) no issues, however I almost never see other charge leads like this and now am wondering why. Obviously its charging fine, but perhaps I'm affecting it's ability to balance even more accurately.

Any thoughts on this from any of you electrical engineers out there?

Cheers!

Luke

Well, first off, I'm not an EE, but do have an Electronics background.....If I understand your concern correctly, you are wondering if having one longer balance lead (i.e. 22") compared to the +- balance leads (i.e. 3") directly at the charger output, will effect the balancing of the 2s batts?

I'm going to say it will be very negligible, and here is why. The amount of current flowing in the balance leads is very small (i.e. 250-500mA), and assuming the resistance of the wire is very small and essentially the same weather you have 3" or 22", the voltage drop across the wire alone will be the same, and small. That being said, the charger would see the same voltages at the balance plug weather it is actually directly at the charger or at the battery.

I don't think you have anything to worry about

Bruce

It won't cause balance issues, but will tend to increase charge time.

The balance readings are affected by not only the voltage drop across the small balance wires, but now also across the long main wires carrying higher current going to the pack from the charger. In many cases it may be considered negligible, but if using the 30 amp capability of the charger with long wires it may be significant.