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early no controllers

Electric Blue auto convertions
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
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Re: early no controllers

Peter C.
My 1977 CitiCar uses 3 contactors (two large & one small).  As I understand
it the smaller one is for starting and slower speeds and one of the larger
ones for full speed (a whopping 35 MPH).  The second larger one is for
reverse when I flip the switch on the dash.
My 1980 Comuta-Van only uses the first two as it is equipped with a 3 speed
(clutch less) standard transmission.  You can see some pictures of the van
setup on Yahoo at:
http://groups.yahoo.com/group/C-Car/photos/album/9282024/pic/2105265578/view?picmode=original&mode=tn&order=ordinal&start=1&dir=asc

Peter Crisitello
Rahway, NJ
[hidden email]





----- Original Message -----
From: "Electric Blue auto convertions" <[hidden email]>
To: <[hidden email]>
Sent: Tuesday, January 15, 2013 11:12 AM
Subject: [EVDL] early no controllers


> 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
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Re: early no controllers

Peter C.
http://www.evalbum.com/3373

If you are not into Yahoo groups, than the above URL in EVAlbums also shows
some pictures of the van as well.  I am intrigued by the 4th contactor for
field weakening!?  Could this extend the range more than the 30 miles
estimated for this vehicle?  Right now I am still trying to figure out all
the cut wires and where they go?!  Wish I had someone here in NJ who could
go over this vehicle with me that actually knows how it works!?

 Peter Crisitello
 Rahway, NJ
 [hidden email]


----- Original Message -----
From: "Peter C." <[hidden email]>
To: "Electric Vehicle Discussion List" <[hidden email]>
Sent: Tuesday, January 15, 2013 11:47 AM
Subject: Re: [EVDL] early no controllers


> My 1977 CitiCar uses 3 contactors (two large & one small).  As I
> understand it the smaller one is for starting and slower speeds and one of
> the larger ones for full speed (a whopping 35 MPH).  The second larger one
> is for reverse when I flip the switch on the dash.
> My 1981 Comuta-Van only uses the first two as it is equipped with a 3
> speed (clutch less) standard transmission.  You can see some pictures of
> the van setup on Yahoo at:
> http://groups.yahoo.com/group/C-Car/photos/album/9282024/pic/2105265578/view?picmode=original&mode=tn&order=ordinal&start=1&dir=asc
>
> Peter Crisitello
> Rahway, NJ
> [hidden email]
>
>
>
>
>
> ----- Original Message -----
> From: "Electric Blue auto convertions" <[hidden email]>
> To: <[hidden email]>
> Sent: Tuesday, January 15, 2013 11:12 AM
> Subject: [EVDL] early no controllers
>
>
>> 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
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Re: early no controllers

Chris Tromley
In reply to this post by Electric Blue auto convertions
On Tue, Jan 15, 2013 at 11:12 AM, Electric Blue auto convertions <
[hidden email]> 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
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Re: early no controllers

Tom Keenan
In reply to this post by Peter C.
With the field weakening setup in my Citicar, it would go faster but consume more watt-hours per mile while activated.  Not hard to implement - just a piece of heavy cable or nichrome strip, a contactor, and a control switch to activate the field weakening contactor.  There are times when it can be used, and times when it should be disabled so the driver has to pay attention to how field weakening is used.

Tom Keenan


On Jan 15, 2013, at 9:18 AM, "Peter C." <[hidden email]> wrote:

> http://www.evalbum.com/3373
>
> If you are not into Yahoo groups, than the above URL in EVAlbums also shows some pictures of the van as well.  I am intrigued by the 4th contactor for field weakening!?  Could this extend the range more than the 30 miles estimated for this vehicle?  Right now I am still trying to figure out all the cut wires and where they go?!  Wish I had someone here in NJ who could go over this vehicle with me that actually knows how it works!?
>
> Peter Crisitello
> Rahway, NJ
> [hidden email]
>
>
> ----- Original Message ----- From: "Peter C." <[hidden email]>
> To: "Electric Vehicle Discussion List" <[hidden email]>
> Sent: Tuesday, January 15, 2013 11:47 AM
> Subject: Re: [EVDL] early no controllers
>
>
>> My 1977 CitiCar uses 3 contactors (two large & one small).  As I understand it the smaller one is for starting and slower speeds and one of the larger ones for full speed (a whopping 35 MPH).  The second larger one is for reverse when I flip the switch on the dash.
>> My 1981 Comuta-Van only uses the first two as it is equipped with a 3 speed (clutch less) standard transmission.  You can see some pictures of the van setup on Yahoo at: http://groups.yahoo.com/group/C-Car/photos/album/9282024/pic/2105265578/view?picmode=original&mode=tn&order=ordinal&start=1&dir=asc
>>
>> Peter Crisitello
>> Rahway, NJ
>> [hidden email]
>>
>>
>>
>>
>>
>> ----- Original Message ----- From: "Electric Blue auto convertions" <[hidden email]>
>> To: <[hidden email]>
>> Sent: Tuesday, January 15, 2013 11:12 AM
>> Subject: [EVDL] early no controllers
>>
>>
>>> 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
>>> -------------- next part --------------
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>
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Re: early no controllers

Lee Hart
In reply to this post by Electric Blue auto convertions
Electric Blue auto convertions wrote:
> When I was working for Clark fork Lifts in the late 60s they didn't
> have controllers as we have today, They used a set of Caps, High
> voltage rectifiers and Xfrmers...

If these controllers made a noticeable whistle, those rectifiers were
SCRs (Silicon Controlled Rectifiers). They were the first truly high
power semiconductors. The controllers worked very much like our modern
ones, but switching speeds were lower, so you heard an audible whistle.
Their efficiency was reasonably good, and they could be very reliable.
It's not hard to find old SCR controllers, still working today.

> 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 controllers looked simple compared to our modern ultracomplex
sensibilities. However, they often had a full set of features that our
modern controllers tend to leave out (field weakening, reverse, regen,
etc.).

> 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.

Resistor control was "old school" even in 1940! Controlling speed with
series resistors was the very first method invented, way back in the
late 1800s! It didn't take long to figure out that it was cheap and
easy, but inefficient.

By the 1900's, EV motor controllers mainly used switches or contactors
to rewire the batteries and motors for series/parallel operation.
Efficient, but speed control was "jumpy".

By the 1930's, they were using field control, so a small rheostat could
regulate a much higher power motor.

--
A truly excellent politician will tell you everything you want to hear.
A truly excellent engineer will tell you the truth. -- D.C. Weber
--
Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
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Re: early no controllers

David Chapman-9
Lee, is the vintage Curtis PMC I have laying around somewhere an SCR controller? I should probably dig it our and try to use it for something like an upgrade to my topless Citicar. Not the perfect solution but would utilize what is just laying around. Dach.




________________________________
 From: Lee Hart <[hidden email]>
To: Electric Vehicle Discussion List <[hidden email]>
Sent: Tuesday, January 15, 2013 8:41 PM
Subject: Re: [EVDL] early no controllers
 
Electric Blue auto convertions wrote:
> When I was working for Clark fork Lifts in the late 60s they didn't
> have controllers as we have today, They used a set of Caps, High
> voltage rectifiers and Xfrmers...

If these controllers made a noticeable whistle, those rectifiers were SCRs (Silicon Controlled Rectifiers). They were the first truly high power semiconductors. The controllers worked very much like our modern ones, but switching speeds were lower, so you heard an audible whistle.
Their efficiency was reasonably good, and they could be very reliable. It's not hard to find old SCR controllers, still working today.

> 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 controllers looked simple compared to our modern ultracomplex sensibilities. However, they often had a full set of features that our modern controllers tend to leave out (field weakening, reverse, regen, etc.).

> 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.

Resistor control was "old school" even in 1940! Controlling speed with series resistors was the very first method invented, way back in the late 1800s! It didn't take long to figure out that it was cheap and easy, but inefficient.

By the 1900's, EV motor controllers mainly used switches or contactors to rewire the batteries and motors for series/parallel operation. Efficient, but speed control was "jumpy".

By the 1930's, they were using field control, so a small rheostat could regulate a much higher power motor.

-- A truly excellent politician will tell you everything you want to hear.
A truly excellent engineer will tell you the truth. -- D.C. Weber
--
Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
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Re: early no controllers

EVDL Administrator
On 15 Jan 2013 at 19:58, David wrote:

> is the vintage Curtis PMC I have laying around somewhere an SCR
> controller?

I trust that if this is in error, someone will correct me.  AFAIK, neither
PMC nor Curtis has ever made an SCR controller.  The early (1970s-1980s) PMC-
branded controllers used bipolar transistors.  The later Curtis controllers
used MOSFETs.  

David Roden
EVDL Administrator
http://www.evdl.org/


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Re: early no controllers

Lee Hart
>> is the vintage Curtis PMC I have laying around somewhere an SCR
>> controller?

EVDL Administrator wrote:
> AFAIK, neither PMC nor Curtis has ever made an SCR controller. The early
> (1970s-1980s) PMC-branded controllers used bipolar transistors. The later
> Curtis controllers used MOSFETs.

That matches my recollection as well. The earliest one I've seen used
power darlington bipolar transistors.

--
The trouble ain't that there's too many fools, but that lightning ain't
distributed right. -- Mark Twain
--
Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
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Re: early no controllers

Lee Hart
In reply to this post by David Chapman-9
On 1/15/2013 9:58 PM, David wrote:
> Lee, is the vintage Curtis PMC I have laying around somewhere an SCR controller? I should probably dig it our and try to use it for something like an upgrade to my topless Citicar. Not the perfect solution but would utilize what is just laying around. Dach.

The earliest PMC controllers I've ever seen were all transistor, not
SCR. They used big darlington transistors. They make the motor "whistle"
like an SCR controller, though they are a bit smaller and more
efficient, as they don't have the big inductors and capacitors.

You still have your Citicar? I thought you were selling it.

--
If you would not be forgotten
When your body's dead and rotten
Then write of great deeds worth the reading
Or do these great deeds, worth repeating.
        -- Ben Franklin, from Poor Richard's Almanac
--
Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
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Re: early no controllers

Lee Hart
In reply to this post by Chris Tromley
On 1/15/2013 7:33 PM, Chris Tromley wrote:
> 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.

Could have been me, or Bob Rice. He was also familiar with these trolley
car controllers.

Some were simple and crude (slow, medium, fast). Others were more
sophisticated, when the routes had more hills and traffic, and thus
required more speed control finesse.

Basically they were big rotary switches. Between the main
slow-medium-fast contacts, there were extra contacts that switched in
resistors to smooth the transitions between speeds, and to provide a
path for inductive currents to flow during the transitions.

> 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.

You can look at the controllers for the 1920's Detroit Electrics to get
an idea what this might look like. They had 7 or more steps, and indeed
acceleration was pretty smooth. There were no resistors except when
starting from a dead stop.

But I don't know about "cheaper", unless you used surplus contactors,
and built it yourself.

--
First they ignore you; then they mock you; then they fight you; then you
win. -- Mahatma Gandhi
--
Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
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Re: early no controllers

Christopher Darilek
In reply to this post by Lee Hart
I plan to use one of these old PMC controllers in my conversion (until it blows up).  Here's the schematic if any one is interested.  It does indeed use transistors, at 1kHz chopping frequency.  Makes AM radio interference that sounds like a Harley Davidson - how's that for an audible EV?

http://4.bp.blogspot.com/-DPY4sZajcTA/UPlnYhw-uOI/AAAAAAAAALY/ZkpKU-eMQ0M/s1600/CurtisPMC.png


I used it previously for 4 1/2 years in a rebuilt Jet Electra.  It's getting old but the insides still look very clean.  I imagine I should worry about the electrolytic caps being dried out but I think I'm just going to let it ride.

-Chris


> The earliest PMC controllers I've ever seen were all transistor, not SCR. They used big darlington transistors. hey make the motor "whistle" like an SCR controller, though they are a bit smaller and more efficient, as they don't have the big inductors and capacitors.
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Re: early no controllers

Lee Hart
Christopher Darilek wrote:
> I plan to use one of these old PMC controllers in my conversion
> (until it blows up).  Here's the schematic if any one is interested.
> http://4.bp.blogspot.com/-DPY4sZajcTA/UPlnYhw-uOI/AAAAAAAAALY/ZkpKU-eMQ0M/s1600/CurtisPMC.png

Too small to read, but it certainly uses bipolar transistors.

> It's getting old but the insides still look very clean. I imagine I
> should worry about the electrolytic caps being dried out but I think
> I'm just going to let it ride.

If the electrolytics fail, they are likely to destroy the rest of the
controller. It may be cheap insurance to replace them first. They are
the least reliable part of the controller.

--
If we knew what we were doing, it wouldn't be called research, would it?
        -- Albert Einstein
--
Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
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Re: early no controllers

Christopher Darilek
> Too small to read, but it certainly uses bipolar transistors.



Here's a bigger one:

http://4.bp.blogspot.com/-XjSe0DMF2HQ/UPmzBOXtEGI/AAAAAAAAAMI/PqrOgSHoHBk/s1600/CurtisPMC_1.jpg

-Chris
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Re: early no controllers

EVDL Administrator
In reply to this post by Christopher Darilek
On 18 Jan 2013 at 7:35, Christopher Darilek wrote:

> I plan to use one of these old PMC controllers in my conversion ...  It does indeed use
> transistors, at 1kHz chopping frequency. ...
>
> http://4.bp.blogspot.com/-DPY4sZajcTA/UPlnYhw-uOI/AAAAAAAAALY/ZkpKU-eMQ0M/s160
> 0/CurtisPMC.png

That looks like the old PMC DCC-96, which came in a more or less shoebox-
shaped package.  Mine was green.  I used it in a Comuta-car.  It had
originally been fitted to a Bradley GT.

I think I recall being told many years ago that the current limiting circuit
for these controllers measured the voltage drop across the transistors (or
maybe just one of them; I'm too lazy to look at the schematic right now).  
As the transistors age, their resistance rises, and the available current
from the controller thus falls.  However, if you try to crank up the current
limit, you're apt to blow the transistors.  So you just have to accept less
power in an aging controller.

I'd also be inclined to replace the caps before trying to use it.  You're
talking about ~35 year old hardware here.  I think the problem is that the
ESR rises with age, but I'm no engineer; Lee Hart can probably tell you
more.

BTW, the DCC-96 manual I have here says it chops at 4kHz, not 1kHz; maybe
yours is even older than mine was.  Or maybe you have a DCC-72?  I didn't
think there was much difference.  FWIW, my later PMC-25 chopped at 2 kHz.

I should scan this DCC manual for the EVDL library one of these days.  I
have the schematic up there, but not the rest of the manual.

David Roden - Akron, Ohio, USA
EVDL Administrator

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