personally i dont liek using big power supplies to charge caps fast. that requires hard hitting CC/CV power supplies that can reliably take dead shorts on their outputs. not many will survive those beatings in the long run.spinningmagnets wrote: ↑Apr 29 2019 8:37amOne of the benefits of using supercapacitors in the kCap is that the battery (or power supply) does not necessarily need to be very high amps and very low resistance, like the nanotech LiPo that was the initial power battery for this design.
Many builders wanted to use a common 12V car battery, but if they did that, it needed to be fairly new so it had low resistance. This is also why the V4 has a power test function, so the builder can tell ahead of time if the battery they plan to use is adequate.
If using only one kCap, I believe the max voltage is 8.2V, but I would have to check that.
for this reason i am using a small 5A 14V power supply to keep the current lifepo4 battery topped up, with constant welding it cant keep up ofcourse but there is way more enough energy in the battery that i will never drain it to notice a power drop.
if i can really crank up to a 8S 40Ah lifepo4 battery then the power is WAY higher then i would be able to get with a kCap setup and it would not require a big power supply to feed those caps to weld at speed, a big battery bank does not have a recovery time like a kCap setup has.
it would be nice to know if something like this has been tested.
its not that i am willing to cheap out but if i already got about 30 big lifepo4 cells on the shelf i can make a battery that will probably destroy any welder i hook it up to. so i am searching for things that would be in favour of having a kCap board versus a huge 30V battery bank.
the only advantage i see is that it is smaller, but it does require a big power supply and might pop the extremely sensitive type A RCD's in my workshop. (yes, its rented to i cant replace it.)