Search found 831 matches

by Njay
Nov 02 2010 5:56pm
Forum: Motor Technology
Topic: Just bougth an 8KW dc motor
Replies: 10
Views: 3512

Re: Just bougth an 8KW dc motor

BlackA, thanks a lot for your good advice. Yes, I've been checking and these are indeed "remanufactured" (whatever that means exactly), but the seller's auction mentions "New". Negative point to him. I inspected the brushes and they all seem new, long (~20mm from tip to the wear mark) , all same len...
by Njay
Oct 31 2010 5:49pm
Forum: Motor Technology
Topic: Just bougth an 8KW dc motor
Replies: 10
Views: 3512

Re: Just bougth an 8KW dc motor

So, no more opinions? If I buy let's say a Mars, will it be of similar quality as the photos above?
by Njay
Oct 29 2010 9:25pm
Forum: Motor Technology
Topic: Just bougth an 8KW dc motor
Replies: 10
Views: 3512

Re: Just bougth an 8KW dc motor

Yes, I bought it on ebay, but the sale says it's new (quoting: "New: A brand-new, unused, unopened and undamaged item in original retail packaging (where packaging is applicable)." ). It doesn't seem new nor unused nor undamaged to me at all, but since it's the first time I have a motor of this powe...
by Njay
Oct 28 2010 6:42pm
Forum: Motor Technology
Topic: Just bougth an 8KW dc motor
Replies: 10
Views: 3512

Just bougth an 8KW dc motor

I just bought one of these, as "New, never used, in the original box". I got what you can see below; what do you think, should I keep it? Click for higher res pics. http://img24.imageshack.us/img24/6010/img8284i.th.jpg http://img713.imageshack.us/img713/4449/img8288k.th.jpg http://img259.imageshack....
by Njay
Sep 14 2010 3:29pm
Forum: E-Bike Technical
Topic: Building the Best Controller
Replies: 340
Views: 42251

Re: Thread Summation Tues 2010-14-10

Kingfish wrote:Comments suggest we can collapse the first two approximately as <100 and > 100.
The higher the working voltage, the more expensive the components. Below 100V you already have a few cost levels.
by Njay
Sep 10 2010 10:07am
Forum: Motor Technology
Topic: The big FET drive challenge
Replies: 34
Views: 4594

Re: The big FET drive challenge

Jeremy, I think the turn-on time is not that critical as it seems, let's say for an N channel. The inductance connected to the MOSFET's drain will prevent "fast" current rise and therefore you do have more time to turn ON. You must, however, make the calculations for your case. At turn-off it is cri...