Jumpy Pots

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Jumpy Pots

Tom H
Hello, I am trying to find out if anyone has had any luck in finding potentiometers that do not degrade with heavy use.  I have tried the Curtis PB-6, a Chinese copy of the PB-6, and the Logisystem potboxes.  All have suffered from the same degradation over time and last no more than 6-8 months in heavy city and suburban driving (about 100 miles a week in stop and go traffic).  The Logisystems potbox lasted only 2 months, the Curtis about 8 months, and the Chinese copy has been in for 6 months and showing signs of degradation.  
Initially all the potentiometers have a steady increase in resistance with the movement of the arm.  However, the pots become progressively “jumpy,” making driving difficult.  I have measured the resistance and find that any small movement of the arm makes the resistance go up much higher for second and then come down to what it should be.  For example, if I have the arm in a position that provides 1000 Ohms of resistance and move it just a few degrees the resistance jumps to 2500 Ohms before coming back down to 1200 Ohms.  This type of jump occurs at any setting of the arm and is not related to the controller.  I have measured this jump when the pot boxes are disconnected from the controller as well.  
So, I am trying to find out if there is a brand of potentiometers that do not have this problem.  I have found out that the resistance in these pots is provided by a piecce of plastic, and I wonder if the plastic degrades with use.  Any help would be welcome.
Thanks,
Tom Hruby
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Re: Jumpy Pots

jonglauser
I've had the same Curtis pot box in my EV for at least 3 years,
possibly up to 14 years old (I bought the car previously converted and
used). Currently my pot box is inside a weatherproof enclosure:

http://picasaweb.google.com/lh/photo/sby8m0mJDgKUTfUMTvYoVA?feat=directlink

it still works smoothly for me on a Kodiak controller

-Jon Glauser
http://jonglauser.blogspot.com
http://www.evalbum.com/555



On Mon, Sep 28, 2009 at 10:31 AM, soundboats <[hidden email]> wrote:

>
> Hello, I am trying to find out if anyone has had any luck in finding
> potentiometers that do not degrade with heavy use.  I have tried the Curtis
> PB-6, a Chinese copy of the PB-6, and the Logisystem potboxes.  All have
> suffered from the same degradation over time and last no more than 6-8
> months in heavy city and suburban driving (about 100 miles a week in stop
> and go traffic).  The Logisystems potbox lasted only 2 months, the Curtis
> about 8 months, and the Chinese copy has been in for 6 months and showing
> signs of degradation.
> Initially all the potentiometers have a steady increase in resistance with
> the movement of the arm.  However, the pots become progressively “jumpy,”
> making driving difficult.  I have measured the resistance and find that any
> small movement of the arm makes the resistance go up much higher for second
> and then come down to what it should be.  For example, if I have the arm in
> a position that provides 1000 Ohms of resistance and move it just a few
> degrees the resistance jumps to 2500 Ohms before coming back down to 1200
> Ohms.  This type of jump occurs at any setting of the arm and is not related
> to the controller.  I have measured this jump when the pot boxes are
> disconnected from the controller as well.
> So, I am trying to find out if there is a brand of potentiometers that do
> not have this problem.  I have found out that the resistance in these pots
> is provided by a piecce of plastic, and I wonder if the plastic degrades
> with use.  Any help would be welcome.
> Thanks,
> Tom Hruby
>
> --
> View this message in context: http://www.nabble.com/Jumpy-Pots-tp25648568p25648568.html
> Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com.
>
>
> _______________________________________________
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>
>

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Re: Jumpy Pots

Matt Lacey
In reply to this post by Tom H
Hi Tom,

Yup, pot boxes will do that.
The bests solution is to change over to Hall effect ones, if your controller
supports it. I have yet to see one of those degrade at all.

Matt

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf
Of soundboats
Sent: Tuesday, 29 September 2009 12:32 AM
To: [hidden email]
Subject: [EVDL] Jumpy Pots


Hello, I am trying to find out if anyone has had any luck in finding
potentiometers that do not degrade with heavy use.  I have tried the Curtis
PB-6, a Chinese copy of the PB-6, and the Logisystem potboxes.  All have
suffered from the same degradation over time and last no more than 6-8
months in heavy city and suburban driving (about 100 miles a week in stop
and go traffic).  The Logisystems potbox lasted only 2 months, the Curtis
about 8 months, and the Chinese copy has been in for 6 months and showing
signs of degradation.  
Initially all the potentiometers have a steady increase in resistance with
the movement of the arm.  However, the pots become progressively "jumpy,"
making driving difficult.  I have measured the resistance and find that any
small movement of the arm makes the resistance go up much higher for second
and then come down to what it should be.  For example, if I have the arm in
a position that provides 1000 Ohms of resistance and move it just a few
degrees the resistance jumps to 2500 Ohms before coming back down to 1200
Ohms.  This type of jump occurs at any setting of the arm and is not related
to the controller.  I have measured this jump when the pot boxes are
disconnected from the controller as well.  
So, I am trying to find out if there is a brand of potentiometers that do
not have this problem.  I have found out that the resistance in these pots
is provided by a piecce of plastic, and I wonder if the plastic degrades
with use.  Any help would be welcome.
Thanks,
Tom Hruby

--
View this message in context:
http://www.nabble.com/Jumpy-Pots-tp25648568p25648568.html
Sent from the Electric Vehicle Discussion List mailing list archive at
Nabble.com.


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Re: Jumpy Pots

Bob Rice-2
In reply to this post by Tom H
  Hi Tom and All;

   Here we go AGAIN! The #$@%^& pots are a crappy way to run
controllers/cars! And since the manufacturers can't seem to find DECENT
ones, or want to spend more than 29 cents for one, but they, like the rest
of us ,WEAR out!They keep on beating dead horses!  The Hall Effect
setup(changing inductance, by throttle position) is Natures most perfect
control; Magnetic fields simply DON'T wear out,period! Sorta like gravity!
It NEVER lets up on us EVers! WHY the Hell hasn't controller builders
haven't gone to OTHER than crappy pots, is beyond me? Let's go back to
piston airliners and steam 20 Century Limiteds? Feh! Had this argument with
Peter Senkowsky about rebuilding Rapture Controllers. MINE that he did for
me, uses a Hall Effect(it LOOKS like a solnoid) and works GREAT! Later he
went BACK to a Pot box, on Dave O.'s Ranger, a step backward? EVery damn
Radio in my house scrapes and scratches on the volume control! I know I'm
SUPPOSED to throw radios away every 2 years, but STILL?

    Not an EE here, WHY is it harder to set up a controller to do Hall
Effect RATHER than a Pot Box??Maybe it's a more difficult design? Maybe
somebody that knows this stuff could chime in? Lee? Got yur ears on? Or
answer this guyz question in the first place,m before I went into Rant mode?

   Seeya

   Bob
----- Original Message -----
From: "soundboats" <[hidden email]>
To: <[hidden email]>
Sent: Monday, September 28, 2009 12:31 PM
Subject: [EVDL] Jumpy Pots


>
> Hello, I am trying to find out if anyone has had any luck in finding
> potentiometers that do not degrade with heavy use.  I have tried the
> Curtis
> PB-6, a Chinese copy of the PB-6, and the Logisystem potboxes.  All have
> suffered from the same degradation over time and last no more than 6-8
> months in heavy city and suburban driving (about 100 miles a week in stop
> and go traffic).  The Logisystems potbox lasted only 2 months, the Curtis
> about 8 months, and the Chinese copy has been in for 6 months and showing
> signs of degradation.
> Initially all the potentiometers have a steady increase in resistance with
> the movement of the arm.  However, the pots become progressively “jumpy,”
> making driving difficult.  I have measured the resistance and find that
> any
> small movement of the arm makes the resistance go up much higher for
> second
> and then come down to what it should be.  For example, if I have the arm
> in
> a position that provides 1000 Ohms of resistance and move it just a few
> degrees the resistance jumps to 2500 Ohms before coming back down to 1200
> Ohms.  This type of jump occurs at any setting of the arm and is not
> related
> to the controller.  I have measured this jump when the pot boxes are
> disconnected from the controller as well.
> So, I am trying to find out if there is a brand of potentiometers that do
> not have this problem.  I have found out that the resistance in these pots
> is provided by a piecce of plastic, and I wonder if the plastic degrades
> with use.  Any help would be welcome.
> Thanks,
> Tom Hruby
>
> --
> View this message in context:
> http://www.nabble.com/Jumpy-Pots-tp25648568p25648568.html
> Sent from the Electric Vehicle Discussion List mailing list archive at
> Nabble.com.
>
>
> _______________________________________________
> General EVDL support: http://evdl.org/help/
> Usage guidelines: http://evdl.org/help/index.html#conv
> Archives: http://evdl.org/archive/
> Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev
>
>

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Re: Jumpy Pots

Roland Wiench
In reply to this post by Tom H
Hello Tom,

I have been running my PB-6 pot with a Zilla 1K for eight years now with no
problem after I rotated the spring tighter to a stop I screw into one of the
screw holes for the cover.

This accelerator action was too light and every time I went over a bump in
the street, I would get a slight increase in motor ampere.  I also added
another accelerator spring which I can adjust as needed to the arm of the
PB-6.

Now after eight years, of driving at the exact same position of the brush
position on the pot which is a steady speed at 30 mph, this spot on the pot
may be more carbon up which increases the resistance and now I get a small
drop in motor ampere. Pushing past that spot, I then get a little jump in
motor ampere.

Its time to take some electronics cleaner to it and see what happens.

Roland

When I hit that same position, I do get a slight increase of motor amps


----- Original Message -----
From: "soundboats" <[hidden email]>
To: <[hidden email]>
Sent: Monday, September 28, 2009 9:31 AM
Subject: [EVDL] Jumpy Pots


>
> Hello, I am trying to find out if anyone has had any luck in finding
> potentiometers that do not degrade with heavy use.  I have tried the
> Curtis
> PB-6, a Chinese copy of the PB-6, and the Logisystem potboxes.  All have
> suffered from the same degradation over time and last no more than 6-8
> months in heavy city and suburban driving (about 100 miles a week in stop
> and go traffic).  The Logisystems potbox lasted only 2 months, the Curtis
> about 8 months, and the Chinese copy has been in for 6 months and showing
> signs of degradation.
> Initially all the potentiometers have a steady increase in resistance with
> the movement of the arm.  However, the pots become progressively “jumpy,”
> making driving difficult.  I have measured the resistance and find that
> any
> small movement of the arm makes the resistance go up much higher for
> second
> and then come down to what it should be.  For example, if I have the arm
> in
> a position that provides 1000 Ohms of resistance and move it just a few
> degrees the resistance jumps to 2500 Ohms before coming back down to 1200
> Ohms.  This type of jump occurs at any setting of the arm and is not
> related
> to the controller.  I have measured this jump when the pot boxes are
> disconnected from the controller as well.
> So, I am trying to find out if there is a brand of potentiometers that do
> not have this problem.  I have found out that the resistance in these pots
> is provided by a piecce of plastic, and I wonder if the plastic degrades
> with use.  Any help would be welcome.
> Thanks,
> Tom Hruby
>
> --
> View this message in context:
> http://www.nabble.com/Jumpy-Pots-tp25648568p25648568.html
> Sent from the Electric Vehicle Discussion List mailing list archive at
> Nabble.com.
>
>
> _______________________________________________
> General EVDL support: http://evdl.org/help/
> Usage guidelines: http://evdl.org/help/index.html#conv
> Archives: http://evdl.org/archive/
> Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev
>
>

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Re: Jumpy Pots

Evan Tuer
In reply to this post by Bob Rice-2
On Mon, Sep 28, 2009 at 5:52 PM, Bob Rice <[hidden email]> wrote:
>  Hi Tom and All;
>
>   Here we go AGAIN! The #$@%^& pots are a crappy way to run
> controllers/cars! And since the manufacturers can't seem to find DECENT
> ones, or want to spend more than 29 cents for one, but they, like the rest
> of us ,WEAR out!They keep on beating dead horses!

Who does?  All the PSA cars use a conductive plastic pot on the
throttle pedal.  They do not wear out.

Top tip: use a good quality conductive plastic pot designed for
throttle pedal position sensing.  Spend at least $30, then forget
about it, because you'll never have to look at it again.

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Re: Jumpy Pots

Matt Lacey
Out of curiosity, what is a PSA car?

Matt

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf
Of Evan Tuer
Sent: Tuesday, 29 September 2009 12:58 AM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Jumpy Pots

On Mon, Sep 28, 2009 at 5:52 PM, Bob Rice <[hidden email]> wrote:
>  Hi Tom and All;
>
>   Here we go AGAIN! The #$@%^& pots are a crappy way to run
> controllers/cars! And since the manufacturers can't seem to find
> DECENT ones, or want to spend more than 29 cents for one, but they,
> like the rest of us ,WEAR out!They keep on beating dead horses!

Who does?  All the PSA cars use a conductive plastic pot on the throttle
pedal.  They do not wear out.

Top tip: use a good quality conductive plastic pot designed for throttle
pedal position sensing.  Spend at least $30, then forget about it, because
you'll never have to look at it again.

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Re: Jumpy Pots

Cor van de Water
Peugeot-Citroen (with double dot on the last e)
http://en.wikipedia.org/wiki/PSA_Group 


Cor van de Water
Director HW & Systems Architecture Group Proxim Wireless
Corporation http://www.proxim.com
Email: [hidden email]    Private: http://www.cvandewater.com
Skype: cor_van_de_water     IM: [hidden email]
Tel: +1 408 383 7626        VoIP: +31 20 3987567 FWD# 25925
Tel: +91 (040)23117400 x203 XoIP: +31877841130

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of Matt Lacey
Sent: Monday, September 28, 2009 11:14 PM
To: 'Electric Vehicle Discussion List'
Subject: Re: [EVDL] Jumpy Pots

Out of curiosity, what is a PSA car?

Matt

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of Evan Tuer
Sent: Tuesday, 29 September 2009 12:58 AM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Jumpy Pots

On Mon, Sep 28, 2009 at 5:52 PM, Bob Rice <[hidden email]> wrote:
>  Hi Tom and All;
>
>   Here we go AGAIN! The #$@%^& pots are a crappy way to run
> controllers/cars! And since the manufacturers can't seem to find
> DECENT ones, or want to spend more than 29 cents for one, but they,
> like the rest of us ,WEAR out!They keep on beating dead horses!

Who does?  All the PSA cars use a conductive plastic pot on the throttle pedal.  They do not wear out.

Top tip: use a good quality conductive plastic pot designed for throttle pedal position sensing.  Spend at least $30, then forget about it, because you'll never have to look at it again.

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Re: Jumpy Pots

Evan Tuer
In reply to this post by Matt Lacey
On Mon, Sep 28, 2009 at 6:44 PM, Matt Lacey <[hidden email]> wrote:
> Out of curiosity, what is a PSA car?

http://en.wikipedia.org/wiki/PSA_Peugeot_Citroën

They made around 20,000 road-going EV versions of their cars and vans.

As I've mentioned before, they use potentiometers from this maker:
http://www.abelectronic.com/electronic-products.html

The CP17 range I believe.   Rated for 3 million cycles.  This
out-lives the car, so it seems to be enough (mine van is at 11 years
old and 80,000 miles, for example).

If you don't fancy that, use a throttle position sensor as found on
any modern IC car.  It's literally made for the job.

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Re: Jumpy Pots

Adrian DeLeon
In reply to this post by Evan Tuer
The conductive pots WILL last longer - auto OEMs use them for throttle  
position sensors (TPS). They're spec'd at 1 million cycles (5 million  
"dither" cycles) and run $30 to $50 or more.

Be sure to check the datasheets before ordering - MOST are guaranteed to  
be linear between 10% and 90% of the listed range. So a 5K pot may not go  
below 500 Ohms or above 4500 Ohms. The sample I tried goes down to 390  
Ohms. This may (or may not) cause your controller to always be a little  
bit ON. It may also trigger a "high pedal lockout" condition on your  
controller. YMMV.

HEPI pedals are awesome! I'm currently using them with Zilla controllers.  
I cut cone pedal off and am using it like a potbox with the original  
throttle cable. The other is a complete pedal mounted on the floorboard.  
Would be nice to disassemble the complete pedals and shove the guts in a  
standard PB-6 box...

-Adrian


On Mon, 28 Sep 2009 09:57:42 -0700, Evan Tuer wrote:

> All the PSA cars use a conductive plastic pot on the
> throttle pedal.  They do not wear out.
>
> Top tip: use a good quality conductive plastic pot designed for
> throttle pedal position sensing.  Spend at least $30, then forget
> about it, because you'll never have to look at it again.
>

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Re: Jumpy Pots

Bob Sisson
Why not put a HE into a Curtis box... HE Pots are cheap enough, its just a
matter of finding one that has the right physical turning range...

http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=1967060&k=Hall%20ef
fect

Bob Sisson
1993 Geo Metro Convertible Project
Gaithersburg MD


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Re: Jumpy Pots

eric@zyxod.com
In reply to this post by Tom H
You have the EV equivalent of "volume knob static" as seen in older
stereo equipment.  We used to fix it with something called "Color TV
Tuner Cleaner" from Radio Shack.  It's just a fluorinated cleaner with a
very small amount of lubricant (mineral oil).  Spray liberally into
pot.  Cleaner will flush out any dirt/gunk, then leave a very thin layer
of lube.

It's now called "TV-Tuner/Control Cleaner & Lubricant"

http://www.radioshack.com/product/index.jsp?productId=2103700

soundboats wrote:

> Hello, I am trying to find out if anyone has had any luck in finding
> potentiometers that do not degrade with heavy use.  I have tried the Curtis
> PB-6, a Chinese copy of the PB-6, and the Logisystem potboxes.  All have
> suffered from the same degradation over time and last no more than 6-8
> months in heavy city and suburban driving (about 100 miles a week in stop
> and go traffic).  The Logisystems potbox lasted only 2 months, the Curtis
> about 8 months, and the Chinese copy has been in for 6 months and showing
> signs of degradation.  
> Initially all the potentiometers have a steady increase in resistance with
> the movement of the arm.  However, the pots become progressively “jumpy,”
> making driving difficult.  I have measured the resistance and find that any
> small movement of the arm makes the resistance go up much higher for second
> and then come down to what it should be.  For example, if I have the arm in
> a position that provides 1000 Ohms of resistance and move it just a few
> degrees the resistance jumps to 2500 Ohms before coming back down to 1200
> Ohms.  This type of jump occurs at any setting of the arm and is not related
> to the controller.  I have measured this jump when the pot boxes are
> disconnected from the controller as well.  
> So, I am trying to find out if there is a brand of potentiometers that do
> not have this problem.  I have found out that the resistance in these pots
> is provided by a piecce of plastic, and I wonder if the plastic degrades
> with use.  Any help would be welcome.
> Thanks,
> Tom Hruby
>
>  

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Re: Jumpy Pots

eric@zyxod.com
In reply to this post by Bob Rice-2
Geez, Bob -- why so *jumpy*?

Bob Rice wrote:
>   Hi Tom and All;
>
>    Here we go AGAIN! The #$@%^& pots are a crappy way to run
>  

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Re: Jumpy Pots

eric@zyxod.com
In reply to this post by Tom H
Will a Honeywell HRS100SSAB090 work in the place of a PB-6 Pot?

soundboats wrote:

> Hello, I am trying to find out if anyone has had any luck in finding
> potentiometers that do not degrade with heavy use.  I have tried the Curtis
> PB-6, a Chinese copy of the PB-6, and the Logisystem potboxes.  All have
> suffered from the same degradation over time and last no more than 6-8
> months in heavy city and suburban driving (about 100 miles a week in stop
> and go traffic).  The Logisystems potbox lasted only 2 months, the Curtis
> about 8 months, and the Chinese copy has been in for 6 months and showing
> signs of degradation.  
> Initially all the potentiometers have a steady increase in resistance with
> the movement of the arm.  However, the pots become progressively “jumpy,”
> making driving difficult.  I have measured the resistance and find that any
> small movement of the arm makes the resistance go up much higher for second
> and then come down to what it should be.  For example, if I have the arm in
> a position that provides 1000 Ohms of resistance and move it just a few
> degrees the resistance jumps to 2500 Ohms before coming back down to 1200
> Ohms.  This type of jump occurs at any setting of the arm and is not related
> to the controller.  I have measured this jump when the pot boxes are
> disconnected from the controller as well.  
> So, I am trying to find out if there is a brand of potentiometers that do
> not have this problem.  I have found out that the resistance in these pots
> is provided by a piecce of plastic, and I wonder if the plastic degrades
> with use.  Any help would be welcome.
> Thanks,
> Tom Hruby
>
>  

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Re: Jumpy Pots

Harris, Lawrence
It's doable, my smart car has an accelerator with I think a pot and it's a 2005 with no sign of age yet at about 350km (200 mi) per week.  You might be able to get the  whole unit from Mercedes parts but I don't know if it's (a) a real pot or a hall effect device and (b) if the range is ok for your needs.  I think it's a real pot as an aftermarket cruise control I saw just plugs into the control wire from the accelerator pedal and a spare port on the back for the speedometer.

Lawrence

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of Eric Poulsen
Sent: Monday, September 28, 2009 3:38 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Jumpy Pots

Will a Honeywell HRS100SSAB090 work in the place of a PB-6 Pot?

soundboats wrote:

> Hello, I am trying to find out if anyone has had any luck in finding
> potentiometers that do not degrade with heavy use.  I have tried the Curtis
> PB-6, a Chinese copy of the PB-6, and the Logisystem potboxes.  All have
> suffered from the same degradation over time and last no more than 6-8
> months in heavy city and suburban driving (about 100 miles a week in stop
> and go traffic).  The Logisystems potbox lasted only 2 months, the Curtis
> about 8 months, and the Chinese copy has been in for 6 months and showing
> signs of degradation.  
> Initially all the potentiometers have a steady increase in resistance with
> the movement of the arm.  However, the pots become progressively “jumpy,”
> making driving difficult.  I have measured the resistance and find that any
> small movement of the arm makes the resistance go up much higher for second
> and then come down to what it should be.  For example, if I have the arm in
> a position that provides 1000 Ohms of resistance and move it just a few
> degrees the resistance jumps to 2500 Ohms before coming back down to 1200
> Ohms.  This type of jump occurs at any setting of the arm and is not related
> to the controller.  I have measured this jump when the pot boxes are
> disconnected from the controller as well.  
> So, I am trying to find out if there is a brand of potentiometers that do
> not have this problem.  I have found out that the resistance in these pots
> is provided by a piecce of plastic, and I wonder if the plastic degrades
> with use.  Any help would be welcome.
> Thanks,
> Tom Hruby
>
>  

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Re: Jumpy Pots

EVDL Administrator
In reply to this post by eric@zyxod.com
On 28 Sep 2009 at 15:25, Eric Poulsen wrote:

> You have the EV equivalent of "volume knob static" as seen in older
> stereo equipment.  We used to fix it with something called "Color TV
> Tuner Cleaner" from Radio Shack.

My experience with this stuff is that in the long run it makes matters
worse.  One can of spray I got at Radio Shack - which I think was called
exactly that - actually partly dissolved the interior of a pot in an audio
amplifier I had.  Vorpal stuff.

The best, safest, and longest-lasting cleaner I know of for potentiometers
(be they in EV or audio use) is the original Cramolin Red.  I still have a
tiny bottle of it that I got almost 20 years ago from Caig when they were
distributing it (Caig's current item, Deoxit, is not the same stuff).  

You use it very, very sparingly; apply it with the tip of a toothpick
(assuming you can get to the inside of the control).  If you use it right,
your kids will inherit your still-mostly-full bottle when you die.

When I checked on it just now, I learned that there is apparently no current
US Cramolin distributor.  They seem to have had some kind of falling-out
with Caig (each side says the other was the bad guys).  Reportedly you can
buy it directly from the factory in Germany, with really high postage
charges, or from farnell.com in the UK.  It's now called Contaclean.

David Roden - Akron, Ohio, USA
EVDL Administrator

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Re: Jumpy Pots

eric@zyxod.com
David Roden wrote:

> On 28 Sep 2009 at 15:25, Eric Poulsen wrote:
>
>  
>> You have the EV equivalent of "volume knob static" as seen in older
>> stereo equipment.  We used to fix it with something called "Color TV
>> Tuner Cleaner" from Radio Shack.
>>    
>
> My experience with this stuff is that in the long run it makes matters
> worse.  One can of spray I got at Radio Shack - which I think was called
> exactly that - actually partly dissolved the interior of a pot in an audio
> amplifier I had.  Vorpal stuff.
>  
Yeah, I forgot to mention that it melts certain plastics, but I don't
think any part of the PB6 assembly is plastic, is it?

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Re: Jumpy Pots

carrott
In reply to this post by Tom H
On Mon, 2009-09-28 at 09:31 -0700, soundboats wrote:
> Hello, I am trying to find out if anyone has had any luck in finding
> potentiometers that do not degrade with heavy use.  I have tried the Curtis
> PB-6, a Chinese copy of the PB-6, and the Logisystem potboxes.  All have
> suffered from the same degradation over time and last no more than 6-8
> months in heavy city and suburban driving (about 100 miles a week in stop
> and go traffic).

I'm having good luck with a VW throttle pedal. It's more complicated
than a simple 0-5k pot so you may have to reconfigure you controller to
talk to it. See
http://carrott.org/cgi-bin/twiki/view/ElectricMini/ThrottlePot I've also
got details there of the Zilla hall effect pedal and a throttle position
sensor style unit from metric mind.

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Re: jumpy Pots

Electric Blue auto convertions
In reply to this post by Tom H


I have only had 3 pots go bad so far and they were with in the first year. NOW if you see what Fork lifts use, the same thing only built much better and are still 5K ohm they last forever, BUT if you call Hyster, Cat, or Clark they want between 50 and 70 $ for the pot itself, is it worth it> thats up to you ..Wayne  ev-blue.com



Hear about Al Gores money from the stim package to build cars in FINLAND !!!!!!!about 1/2 a Bill $
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Re: Jumpy Pots

Tom H
In reply to this post by eric@zyxod.com
Eric and others - thanks for all your input. It has has been a very interesting discussion.  I believe that the current pots (PB-6, their replacements and the Honeywell ones) are  made with a plastic resistive element.  This is what I was able to find in researching the issue. So, I would steer away from using the TV cleaners.  

I will explore some of the options suggested:
1. check out pots from fork lifts
2. check out throttle position sensors from autos
3. find out if the Logisystem controller I have can be run with a Hall effect sensor
4. Check out cleaning the pots with Cramolin red.  I still  have my two old pots that have gone bad, so cleaning one and checking it is no extra cost for me.

Tom Hruby
Eric Poulsen wrote
David Roden wrote:
> On 28 Sep 2009 at 15:25, Eric Poulsen wrote:
>
>  
>> You have the EV equivalent of "volume knob static" as seen in older
>> stereo equipment.  We used to fix it with something called "Color TV
>> Tuner Cleaner" from Radio Shack.
>>    
>
> My experience with this stuff is that in the long run it makes matters
> worse.  One can of spray I got at Radio Shack - which I think was called
> exactly that - actually partly dissolved the interior of a pot in an audio
> amplifier I had.  Vorpal stuff.
>  
Yeah, I forgot to mention that it melts certain plastics, but I don't
think any part of the PB6 assembly is plastic, is it?

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