crock pot mods
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crock pot mods

 
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Flx Cpy
Guest





Posted: Sat Mar 19, 2005 1:25 pm    Post subject: crock pot mods Reply with quote

Bonehead question...How can I take down the level of heat on a crock
pot? Is this just a resister? It has a temp control with 3 settings
but it isn't really take-apart-able...and I only want to try if it is
possible. Hopefully someone here can tell me if it is possible.
Thanks!

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DaveC
Guest





Posted: Sat Mar 19, 2005 2:16 pm    Post subject: Re: crock pot mods Reply with quote

On Sat, 19 Mar 2005 07:25:23 +0000, Flx Cpy wrote
(in article <1111217123.279877.199260@z14g2000cwz.googlegroups.com>):

Quote:
Bonehead question...How can I take down the level of heat on a crock
pot? Is this just a resister? It has a temp control with 3 settings
but it isn't really take-apart-able...and I only want to try if it is
possible. Hopefully someone here can tell me if it is possible.

A diode in series with the mains supply will halve the power supplied to the
heating element.

You have to decide if this is 1) safe in your application, 2) wise for you to
attempt 3) if you have the skills to do, and ... many other things of which i
can't think right now.
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group
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Bob Masta
Guest





Posted: Sat Mar 19, 2005 9:05 pm    Post subject: Re: crock pot mods Reply with quote

On 18 Mar 2005 23:25:23 -0800, "Flx Cpy" <flxcpy@yahoo.com> wrote:

Quote:
Bonehead question...How can I take down the level of heat on a crock
pot? Is this just a resister? It has a temp control with 3 settings
but it isn't really take-apart-able...and I only want to try if it is
possible. Hopefully someone here can tell me if it is possible.
Thanks!


This is actually a rather interesting question. My guess is that
the crock pot uses an "infinity" control, as in an electric range
or oven. Full mains power is appied to the element through a
bimetallic strip. The strip heats up and bends, breaking contact.
The strip cools down and restores contact. When you turn
the temperature control, you are applying a mechanical load
that biases the strip.

So, if you reduce the mains supply via a diode or lamp dimmer,
what will happen? I'd imagine that for modest reduction there
might be no change in temperature; the strip would just cycle
less to maintain the same total heating. But eventually, if
you reduce the input below the point where the strip never
gets hot enough to break contact, then the heating would
be proportional to the input. The question is then where
this point is, relative to your reduced power needs. Might
be worth a test, if you are really determined not to take it
apart. But if you can figure out how to get it open, or
at least get to the control behind the knob, you might be
able to tweak the bias load mechanism to get any heat
you want.

Best regards


Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com

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Robert Monsen
Guest





Posted: Sun Mar 20, 2005 12:42 am    Post subject: Re: crock pot mods Reply with quote

Bob Masta wrote:
Quote:
On 18 Mar 2005 23:25:23 -0800, "Flx Cpy" <flxcpy@yahoo.com> wrote:


Bonehead question...How can I take down the level of heat on a crock
pot? Is this just a resister? It has a temp control with 3 settings
but it isn't really take-apart-able...and I only want to try if it is
possible. Hopefully someone here can tell me if it is possible.
Thanks!



This is actually a rather interesting question. My guess is that
the crock pot uses an "infinity" control, as in an electric range
or oven. Full mains power is appied to the element through a
bimetallic strip. The strip heats up and bends, breaking contact.
The strip cools down and restores contact. When you turn
the temperature control, you are applying a mechanical load
that biases the strip.

So, if you reduce the mains supply via a diode or lamp dimmer,
what will happen? I'd imagine that for modest reduction there
might be no change in temperature; the strip would just cycle
less to maintain the same total heating. But eventually, if
you reduce the input below the point where the strip never
gets hot enough to break contact, then the heating would
be proportional to the input. The question is then where
this point is, relative to your reduced power needs. Might
be worth a test, if you are really determined not to take it
apart. But if you can figure out how to get it open, or
at least get to the control behind the knob, you might be
able to tweak the bias load mechanism to get any heat
you want.


If it is one of these 'infinity controls', then the resistance between
the leads when it isn't plugged in will be the same, low, no matter what
the setting, right?

If it is some scheme for limiting the duty cycle through the heating
elements using a triac or relay, then the resistance will probably be
very large.

If they are switching in more elements, then the resistance will vary
depending on the setting.

1 and 3 will allow the lamp dimmer or diode, 2 will not, I think.

--
Regards,
Robert Monsen

"Your Highness, I have no need of this hypothesis."
- Pierre Laplace (1749-1827), to Napoleon,
on why his works on celestial mechanics make no mention of God.
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John Fields
Guest





Posted: Sun Mar 20, 2005 1:39 am    Post subject: Re: crock pot mods Reply with quote

On 18 Mar 2005 23:25:23 -0800, "Flx Cpy" <flxcpy@yahoo.com> wrote:

Quote:
Bonehead question...How can I take down the level of heat on a crock
pot? Is this just a resister? It has a temp control with 3 settings
but it isn't really take-apart-able...and I only want to try if it is
possible. Hopefully someone here can tell me if it is possible.

---
Since you only want to _lower_ the heat, you might want to try putting
it on high and using a simple lamp dimmer to take it down from there.
Make sure the wattage rating of the lamp dimmer is greater than or
equal to the wattage rating of the crock pot.

--
John Fields
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Rich Grise
Guest





Posted: Wed Mar 23, 2005 2:52 am    Post subject: Re: crock pot mods Reply with quote

On Sat, 19 Mar 2005 10:42:29 -0800, Robert Monsen wrote:
Quote:
Bob Masta wrote:
On 18 Mar 2005 23:25:23 -0800, "Flx Cpy" <flxcpy@yahoo.com> wrote:

Bonehead question...How can I take down the level of heat on a crock
pot? Is this just a resister? It has a temp control with 3 settings
but it isn't really take-apart-able...and I only want to try if it is
possible. Hopefully someone here can tell me if it is possible.

This is actually a rather interesting question. My guess is that
the crock pot uses an "infinity" control, as in an electric range

If it is one of these 'infinity controls', then the resistance between
the leads when it isn't plugged in will be the same, low, no matter what
the setting, right?

I'd almost bet it's not one, since it has three settings, not a continuous
control. In which case, it's probably two elements.

Like Robert said, check the resistance.

Or, you could try a 250W light bulb in series, and see what happens -
that will definitely tell you if it's got a thermostat!

And, if it's just the two elements, steady on (this is how those
little electric space heaters work), then a lamp dimmer should be
fine.

Good Luck!
Rich
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