Originally Posted by
t.s.davis
there's the problem. Speedo can't do that. There's no way for it to do that.
The packs should drain the same.......but only if they are of the same quality. If even one cell in either packs is weak it screws up the whole thing. This is the risk with less expensive packs. Usually it's fine if a cell is delivering lower voltage in say a revolt running 65 amps or so. You might not notice a weak cell. The boat will likely be slow.........er. When you start drawing 175+ amps that weak cell can make a mess. It gets hot. Increasing it's internal resistance. Which makes the whole system worse. At the end of the run your cells will be hot as hell trying to in effect balance voltages between the cells during the run. It's like trying to run a foot race only someone stuck a knife in one of your legs. Weak leg makes the other leg do all the work. The good leg can't do it alone. Feel'n the burn?
Another risk with the budget packs is internal resistance. If internal resistance is super high on again, just one cell. Screws up the whole works. The other cells have to make up the difference. Back to the foot race. One leg has a cramp. Not only is it useless but your good leg is on fire from the extra work.
The lvc might have bought you time but the heat would still have destroyed the entire system eventually.
I don't think i've hit an lvc since nimh days. Maybe i just have a mental timer that makes me stop in time. Although, i'm hearing that the premature lvc on my sw120 may have been causing problems for my son in lsh. Not done messing with that.
Guys, there's nothing wrong with buying cheaper packs. Turnigy, zippy, etc. You just have to accept the risk that comes with them. There is a failure potential. It isn't a given though. Some of them are awesome. Imho the cheaper packs require the knowledge to recognize when and more importantly why something isn't working. Unfortunately, the cheaper packs are purchased by guys that can't justify the good ones. "i'm just a back yard basher, i don't want to race" guy is who ends up with them. They don't have knowledge or the equipment to figure the danged things out. That's not a criticism by the way.
Example. Doby had some fresh packs for the nats. They were of the less expensive variety. Voltage was equal when i checked them two weeks earlier. By race day he had a cell drop out of a pack. Voltage was low on just one cell if i remember correctly. He knows what the potential impact is sssso......he didn't race them. Knowledge wins again. Woohoo
the key to this example is that john knew he needed to check them before he threw a gozillion amps at them.
Dang, wrote a novel. Sorry guys. I type fast.
^^^^^this
32" carbon rivercat single 4s 102mph, 27” mini Rivercat 92mph, kbb34 91mph, jessej micro cat(too fast) was
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