On Tue, Jan 15, 2013 at 11:12 AM, Electric Blue auto convertions <
[email protected]> wrote:

> When I was working for Clark fork Lifts in the late 60s they didnt have
> controllers as we have today, They used a set of Caps, High voltage
> rectifiers and Xfrmers , The Xfmers /caps could go as high as 300 volts on
> a 48 volt battery system, there was 4 large contactors , one was reversing,
> one was for field weakening , They had what was a very rudimentary
> "controller" only about 5 or 6 resistors a few diodes and some small caps ,
> this went to the "gas peddle" the large Recs could handle over 1,000 amps .
> The earliest electric fork lift I worked on was from the early 40s, It had
> a "gear shift" lever that hit 3 different resistors, "large" for different
> speeds, and one reversing contactor,, simple and it was still in use way
> back when I had to rebuild the motor,,,, brushes and clean the Com +
> springs , thats all it needed


I remember a post years ago (maybe from Lee?) about speed controls on
trolley cars that were quite smooth and sophisticated.  I think it was a
drum-style multiple position switch with all sorts of clever enhancements
to transition from stage to stage, ensure you couldn't engage two stations,
etc.

With the cost of modern solid-state controllers, I have to wonder if you
couldn't make a really slick mechanical controller.  With enough stages it
would be almost as smooth, more efficient, and a lot cheaper.

Chris
LeSled is for sale!
http://www.evalbum.com/274
-------------- next part --------------
An HTML attachment was scrubbed...
URL: 
<http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20130115/237d79db/attachment.htm>
_______________________________________________
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
http://lists.evdl.org/listinfo.cgi/ev-evdl.org
For EV drag racing discussion, please use NEDRA 
(http://groups.yahoo.com/group/NEDRA)

Reply via email to