Matthew Parkhouse, RN [email protected]
> On 8 Jan 2017, at 10:44, Lee Hart via EV <[email protected]> wrote: > > brucedp5 via EV wrote: >> You are on the road again using another cursit controller. But for how long? >> After my first curtis (cursit) controller died, and was replaced with >> another by the converter... [it died again] > > Bruce, there's a bit more to the story: > > - This was about 15-20 years ago > - You were driving a heavy on-road vehicle > - You were using the smaller Curtis 1221, not the 1231 > > The Curtis 1221 was designed for industrial forklifts -- not on-road EVs. EV > usage is harder on the controller, because it is being asked to deliver > higher speeds and higher horsepower. It also has to survive in a harsher > environment; outdoors in all kinds of weather. > > EV converters tend to "push" thing beyond their ratings, to save money or get > by with what was handy at the time. They often use parts right at their > absolute maximum ratings... no margin for error. If you use a 72-120v > controller *at* 120v, it's going to fail sooner rather than later. > > The 1221's were overloaded, and they failed. Curtis thus came out with the > 1232, and improved version built for on-road EV use. > > The failure mode of your second controller sounds like a capacitor blew. That > throws conductive goo and aluminum foil all over the place inside the case. > This causes all sorts of additional short circuits and smoke and fire. > > My guess is that you were just off charge, so the pack voltage was higher > than 120v. Your EV converter may have installed a used or old or > lower-voltage Curtis 1221, whose capacitors weren't up to the task. Bang! > >> If having a lead foot (strong acceleration use) with the cursit will cause a >> controller failure sooner, then isn't there a simple RC (resistor, >> capacitor) circuit one could put at the cursit controller (pot-box) input >> (slows the acceleration attack ramp to a slower rise, etc.)? > > The Curtis has user-adjustable trimpots for current limit and acceleration > ramp-up. But as you might expect, most of the time someone has turned them up > to maximum. This is the go-fast / die-young setting. > -- > Teaching children to program goes against the grain of modern education. > Just imagine the chaos if they learned to think logically, plan, create, > implement, test, and execute! > -- > Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > Read EVAngel's EV News at http://evdl.org/evln/ > Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA) > _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
