Peltier devices

[F Murtz]

Anyone know about peltier devices? Can you drive them at half voltage?
I wish to make a container that is limited to between 18 and 20
centigrade and apparently they do not like to be cycled much for temp
control,I would rather have it on constantly but at less than full
capabilities.

 

[F Murtz]

F Murtz wrote:

Anyone know about peltier devices? Can you drive them at half voltage?
I wish to make a container that is limited to between 18 and 20
centigrade and apparently they do not like to be cycled much for temp
control,I would rather have it on constantly but at less than full
capabilities.

On further musing I would probably still have problems as the system is
dependent on ambient temp so I would probably have to have a temp sw to
switch on only when ambient is higher.

 

[Computer Nerd Kev]

F Murtz <haggisz@hotmail.com> wrote:

F Murtz wrote:
Anyone know about peltier devices? Can you drive them at half voltage?
I wish to make a container that is limited to between 18 and 20
centigrade and apparently they do not like to be cycled much for temp
control,I would rather have it on constantly but at less than full
capabilities.

Based on how special Peltier driver devices like this:
https://www.maximintegrated.com/en/products/power/switching-regulators/MAX1968.html
appear to work, it seems that they should function with varying voltage
levels.

More information about Peltier devices here, probably more than required
for your application:
https://www.maximintegrated.com/en/app-notes/index.mvp/id/3318

On further musing I would probably still have problems as the system is
dependent on ambient temp so I would probably have to have a temp sw to
switch on only when ambient is higher.

Wouldn't you want it to heat the container then, in order to keep it close
to a "perfect" temperature? H-bridge circuits such as used in motor control
circuits appear to be commonly used for this purpose, in order to reverse
the current flow.

--
__ __
#_ < |\| |< _#

 

[Wayne Chirnside]

On Thu, 17 Dec 2015 12:01:37 +1100, F Murtz wrote:

F Murtz wrote:
Anyone know about peltier devices? Can you drive them at half voltage?
I wish to make a container that is limited to between 18 and 20
centigrade and apparently they do not like to be cycled much for temp
control,I would rather have it on constantly but at less than full
capabilities.

On further musing I would probably still have problems as the system is
dependent on ambient temp so I would probably have to have a temp sw to
switch on only when ambient is higher.

You want a clean supply, no ripple.
Yes you can get different levels of cooling with less current.

A thermostat available through www.aliexpress.com for about 4$ U.S. can
regulate the temperature with hystersis.

The thermostat I'm thinking of was reviewed and given good marks by
www.bigclive.com

 

[~misfit~]

Once upon a time on usenet Wayne Chirnside wrote:

On Thu, 17 Dec 2015 12:01:37 +1100, F Murtz wrote:

F Murtz wrote:
Anyone know about peltier devices? Can you drive them at half
voltage? I wish to make a container that is limited to between 18
and 20 centigrade and apparently they do not like to be cycled much
for temp control,I would rather have it on constantly but at less
than full capabilities.

On further musing I would probably still have problems as the system
is dependent on ambient temp so I would probably have to have a temp
sw to switch on only when ambient is higher.

You want a clean supply, no ripple.
Yes you can get different levels of cooling with less current.

A thermostat available through www.aliexpress.com for about 4$ U.S.
can regulate the temperature with hystersis.

The thermostat I'm thinking of was reviewed and given good marks by
www.bigclive.com

Can you be any more cryptic? I clicked both links and after several minutes
couldn't find what you were talking about.

(I bought a peltier a while ago to make a 'butter conditioner' - a device
for keeping butter at that perfect spreading temperature but don't yet have
control electronics for it.)
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)

 

[Wayne Chirnside]

On Sat, 19 Dec 2015 12:48:29 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Thu, 17 Dec 2015 12:01:37 +1100, F Murtz wrote:

F Murtz wrote:
Anyone know about peltier devices? Can you drive them at half
voltage? I wish to make a container that is limited to between 18
and 20 centigrade and apparently they do not like to be cycled much
for temp control,I would rather have it on constantly but at less
than full capabilities.

On further musing I would probably still have problems as the system
is dependent on ambient temp so I would probably have to have a temp
sw to switch on only when ambient is higher.

You want a clean supply, no ripple.
Yes you can get different levels of cooling with less current.

A thermostat available through www.aliexpress.com for about 4$ U.S.
can regulate the temperature with hystersis.

The thermostat I'm thinking of was reviewed and given good marks by
www.bigclive.com

Can you be any more cryptic? I clicked both links and after several
minutes couldn't find what you were talking about.

The gentleman in question has youtube video where he describes the precise
steps to program the module widely available at www.aliexpress.com for
around 4$ and slightly under.
So search his videos for that then on to aliexpress too order one.
I used cclive in linux to download the youtube so as to have the
programming instructions locally.

(I bought a peltier a while ago to make a 'butter conditioner' - a
device for keeping butter at that perfect spreading temperature but
don't yet have control electronics for it.)

$4

 

[~misfit~]

Once upon a time on usenet Wayne Chirnside wrote:

On Sat, 19 Dec 2015 12:48:29 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Thu, 17 Dec 2015 12:01:37 +1100, F Murtz wrote:

F Murtz wrote:
Anyone know about peltier devices? Can you drive them at half
voltage? I wish to make a container that is limited to between
18 and 20 centigrade and apparently they do not like to be cycled
much for temp control,I would rather have it on constantly but at
less than full capabilities.

On further musing I would probably still have problems as the
system is dependent on ambient temp so I would probably have to
have a temp sw to switch on only when ambient is higher.

You want a clean supply, no ripple.
Yes you can get different levels of cooling with less current.

A thermostat available through www.aliexpress.com for about 4$ U.S.
can regulate the temperature with hystersis.

The thermostat I'm thinking of was reviewed and given good marks by
www.bigclive.com

Can you be any more cryptic? I clicked both links and after several
minutes couldn't find what you were talking about.

The gentleman in question has youtube video where he describes the
precise steps to program the module widely available at
www.aliexpress.com for around 4$ and slightly under.
So search his videos for that then on to aliexpress too order one.
I used cclive in linux to download the youtube so as to have the
programming instructions locally.

Can you please tell me the title of the video? That would make it easier to
find. I've just scrolled through nearly a dozen pages of bigclive videos on
youtube and can't find it. Searches using his name, 'thermostat',
'aliexpress' '$4' and various permuatations of those don't give me the
desired result.

(I bought a peltier a while ago to make a 'butter conditioner' - a
device for keeping butter at that perfect spreading temperature but
don't yet have control electronics for it.)

$4

Yep, I'm ready and willing to order it when I can find it.
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)

 

[F Murtz]

~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Sat, 19 Dec 2015 12:48:29 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Thu, 17 Dec 2015 12:01:37 +1100, F Murtz wrote:

F Murtz wrote:
Anyone know about peltier devices? Can you drive them at half
voltage? I wish to make a container that is limited to between
18 and 20 centigrade and apparently they do not like to be cycled
much for temp control,I would rather have it on constantly but at
less than full capabilities.

On further musing I would probably still have problems as the
system is dependent on ambient temp so I would probably have to
have a temp sw to switch on only when ambient is higher.

You want a clean supply, no ripple.
Yes you can get different levels of cooling with less current.

A thermostat available through www.aliexpress.com for about 4$ U.S.
can regulate the temperature with hystersis.

The thermostat I'm thinking of was reviewed and given good marks by
www.bigclive.com

Can you be any more cryptic? I clicked both links and after several
minutes couldn't find what you were talking about.

The gentleman in question has youtube video where he describes the
precise steps to program the module widely available at
www.aliexpress.com for around 4$ and slightly under.
So search his videos for that then on to aliexpress too order one.
I used cclive in linux to download the youtube so as to have the
programming instructions locally.


Can you please tell me the title of the video? That would make it easier to
find. I've just scrolled through nearly a dozen pages of bigclive videos on
youtube and can't find it. Searches using his name, 'thermostat',
'aliexpress' '$4' and various permuatations of those don't give me the
desired result.

(I bought a peltier a while ago to make a 'butter conditioner' - a
device for keeping butter at that perfect spreading temperature but
don't yet have control electronics for it.)

$4

Yep, I'm ready and willing to order it when I can find it.

I gave up looking, there was a thermostat for around $4.00 among the
more expensive ones, but nothing said about peltier the expensive ones
mentioned controlling peltier.

 

[Wayne Chirnside]

On Mon, 21 Dec 2015 21:13:25 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Sat, 19 Dec 2015 12:48:29 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Thu, 17 Dec 2015 12:01:37 +1100, F Murtz wrote:

F Murtz wrote:
Anyone know about peltier devices? Can you drive them at half
voltage? I wish to make a container that is limited to between 18
and 20 centigrade and apparently they do not like to be cycled much
for temp control,I would rather have it on constantly but at less
than full capabilities.

On further musing I would probably still have problems as the system
is dependent on ambient temp so I would probably have to have a temp
sw to switch on only when ambient is higher.

You want a clean supply, no ripple.
Yes you can get different levels of cooling with less current.

A thermostat available through www.aliexpress.com for about 4$ U.S.
can regulate the temperature with hystersis.

The thermostat I'm thinking of was reviewed and given good marks by
www.bigclive.com

Can you be any more cryptic? I clicked both links and after several
minutes couldn't find what you were talking about.

The gentleman in question has youtube video where he describes the
precise steps to program the module widely available at
www.aliexpress.com for around 4$ and slightly under.
So search his videos for that then on to aliexpress too order one.
I used cclive in linux to download the youtube so as to have the
programming instructions locally.


Can you please tell me the title of the video?

Just wasted an hour looking.

That would make it easier
to find. I've just scrolled through nearly a dozen pages of bigclive
videos on youtube and can't find it. Searches using his name,
'thermostat', 'aliexpress' '$4' and various permuatations of those don't
give me the desired result.

http://www.aliexpress.com/item/Freeshipping-W1209-Mini-thermostat-
Temperature-controller-Incubation-thermostat-temperature-control-
switch/32225252366.html

Not certain if I've used this vendor or not but the unit is ubiquitous on
aliexpress and my experiences so far of some 70 orders 100 percent.

(I bought a peltier a while ago to make a 'butter conditioner' - a
device for keeping butter at that perfect spreading temperature but
don't yet have control electronics for it.)

$4

Yep, I'm ready and willing to order it when I can find it.

http://www.aliexpress.com/item/Freeshipping-W1209-Mini-thermostat-
Temperature-controller-Incubation-thermostat-temperature-control-
switch/32225252366.html

One vendor among many.
I'm buying five from a different vendor.
Do you think $1.90 to much to pay...

 

[~misfit~]

Once upon a time on usenet Wayne Chirnside wrote:

On Mon, 21 Dec 2015 21:13:25 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Sat, 19 Dec 2015 12:48:29 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Thu, 17 Dec 2015 12:01:37 +1100, F Murtz wrote:

F Murtz wrote:
Anyone know about peltier devices? Can you drive them at half
voltage? I wish to make a container that is limited to
between 18 and 20 centigrade and apparently they do not like to
be cycled much for temp control,I would rather have it on
constantly but at less than full capabilities.

On further musing I would probably still have problems as the
system is dependent on ambient temp so I would probably have to
have a temp sw to switch on only when ambient is higher.

You want a clean supply, no ripple.
Yes you can get different levels of cooling with less current.

A thermostat available through www.aliexpress.com for about 4$
U.S. can regulate the temperature with hystersis.

The thermostat I'm thinking of was reviewed and given good marks
by www.bigclive.com

Can you be any more cryptic? I clicked both links and after several
minutes couldn't find what you were talking about.

The gentleman in question has youtube video where he describes the
precise steps to program the module widely available at
www.aliexpress.com for around 4$ and slightly under.
So search his videos for that then on to aliexpress too order one.
I used cclive in linux to download the youtube so as to have the
programming instructions locally.


Can you please tell me the title of the video?

Just wasted an hour looking.

That would make it easier
to find. I've just scrolled through nearly a dozen pages of bigclive
videos on youtube and can't find it. Searches using his name,
'thermostat', 'aliexpress' '$4' and various permuatations of those
don't give me the desired result.

http://www.aliexpress.com/item/Freeshipping-W1209-Mini-thermostat-
Temperature-controller-Incubation-thermostat-temperature-control-
switch/32225252366.html

Not certain if I've used this vendor or not but the unit is
ubiquitous on aliexpress and my experiences so far of some 70 orders
100 percent.


(I bought a peltier a while ago to make a 'butter conditioner' - a
device for keeping butter at that perfect spreading temperature but
don't yet have control electronics for it.)

$4

Yep, I'm ready and willing to order it when I can find it.

http://www.aliexpress.com/item/Freeshipping-W1209-Mini-thermostat-
Temperature-controller-Incubation-thermostat-temperature-control-
switch/32225252366.html

One vendor among many.
I'm buying five from a different vendor.
Do you think $1.90 to much to pay...

I also gave up searching clive's stuff yesterday and settled for ordering a
few of those from Aliexpress.
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)

 

[F Murtz]

~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Mon, 21 Dec 2015 21:13:25 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Sat, 19 Dec 2015 12:48:29 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Thu, 17 Dec 2015 12:01:37 +1100, F Murtz wrote:

F Murtz wrote:
Anyone know about peltier devices? Can you drive them at half
voltage? I wish to make a container that is limited to
between 18 and 20 centigrade and apparently they do not like to
be cycled much for temp control,I would rather have it on
constantly but at less than full capabilities.

On further musing I would probably still have problems as the
system is dependent on ambient temp so I would probably have to
have a temp sw to switch on only when ambient is higher.

You want a clean supply, no ripple.
Yes you can get different levels of cooling with less current.

A thermostat available through www.aliexpress.com for about 4$
U.S. can regulate the temperature with hystersis.

The thermostat I'm thinking of was reviewed and given good marks
by www.bigclive.com

Can you be any more cryptic? I clicked both links and after several
minutes couldn't find what you were talking about.

The gentleman in question has youtube video where he describes the
precise steps to program the module widely available at
www.aliexpress.com for around 4$ and slightly under.
So search his videos for that then on to aliexpress too order one.
I used cclive in linux to download the youtube so as to have the
programming instructions locally.


Can you please tell me the title of the video?

Just wasted an hour looking.

That would make it easier
to find. I've just scrolled through nearly a dozen pages of bigclive
videos on youtube and can't find it. Searches using his name,
'thermostat', 'aliexpress' '$4' and various permuatations of those
don't give me the desired result.

http://www.aliexpress.com/item/Freeshipping-W1209-Mini-thermostat-
Temperature-controller-Incubation-thermostat-temperature-control-
switch/32225252366.html

Not certain if I've used this vendor or not but the unit is
ubiquitous on aliexpress and my experiences so far of some 70 orders
100 percent.


(I bought a peltier a while ago to make a 'butter conditioner' - a
device for keeping butter at that perfect spreading temperature but
don't yet have control electronics for it.)

$4

Yep, I'm ready and willing to order it when I can find it.

http://www.aliexpress.com/item/Freeshipping-W1209-Mini-thermostat-
Temperature-controller-Incubation-thermostat-temperature-control-
switch/32225252366.html

One vendor among many.
I'm buying five from a different vendor.
Do you think $1.90 to much to pay...

I also gave up searching clive's stuff yesterday and settled for ordering a
few of those from Aliexpress.

I ordered a couple also but the probably will get used for something
else don't know whether they would be suitable for peltier control
Did not find the video where the steps to program the device was
especially referring to peltier

 

[Wayne Chirnside]

On Wed, 23 Dec 2015 12:44:55 +1100, F Murtz wrote:

:13:25 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Sat, 19 Dec 2015 12:4

Big Clive reviews cheap Chinese thermostat.

https://www.youtube.com/watch?v=yVD0zkZTe00

Took me all of two minutes to find after not finding it on my local drive.

 

[~misfit~]

Once upon a time on usenet Wayne Chirnside wrote:

On Wed, 23 Dec 2015 12:44:55 +1100, F Murtz wrote:

13:25 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Sat, 19 Dec 2015 12:4

Big Clive reviews cheap Chinese thermostat.

https://www.youtube.com/watch?v=yVD0zkZTe00

Took me all of two minutes to find after not finding it on my local
drive.

I saw that in the search results but ignored it as you specifically said the
thermostat came from Aliexpress.
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)

 

[F Murtz]

Wayne Chirnside wrote:

On Wed, 23 Dec 2015 12:44:55 +1100, F Murtz wrote:

:13:25 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Sat, 19 Dec 2015 12:4

Big Clive reviews cheap Chinese thermostat.

https://www.youtube.com/watch?v=yVD0zkZTe00

Took me all of two minutes to find after not finding it on my local drive.

Thanks,interesting, but no reference to peltier, will just have to
experiment

 

[Wayne Chirnside]

On Thu, 24 Dec 2015 12:34:16 +1100, F Murtz wrote:

Wayne Chirnside wrote:
On Wed, 23 Dec 2015 12:44:55 +1100, F Murtz wrote:

:13:25 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Sat, 19 Dec 2015 12:4

Big Clive reviews cheap Chinese thermostat.

https://www.youtube.com/watch?v=yVD0zkZTe00

Took me all of two minutes to find after not finding it on my local
drive.

Thanks,interesting, but no reference to peltier, will just have to
experiment

I have eight peltiers here.

What they care about is smooth power, no ripple.
Then the thermostat is just a switch not caring what it is attached to as
long as the relay amperage does not get exceeded.

just set an appropriate hystersis.

 

[Wayne Chirnside]

On Thu, 24 Dec 2015 18:39:35 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Wed, 23 Dec 2015 12:44:55 +1100, F Murtz wrote:

13:25 +1300, ~misfit~ wrote:

Once upon a time on usenet Wayne Chirnside wrote:
On Sat, 19 Dec 2015 12:4

Big Clive reviews cheap Chinese thermostat.

https://www.youtube.com/watch?v=yVD0zkZTe00

Took me all of two minutes to find after not finding it on my local
drive.

I saw that in the search results but ignored it as you specifically said
the thermostat came from Aliexpress.

The Chinese make these things in volume, he got his ebay.uk

I got mine, more cheaply, at aliexpress.

I referred to Big Clive because his was the explanation as to how to
program the device.

To date I've never had a problem with a vendor on that site though I do
have to wait a bit for the item to cross the Pacific in a container.

I also downloaded the programming instructions using the Linux cclive
youtube downloader for future reference should I forget the first button
cycles through the various parameters to be set.

hystersis being of some importance with a peltier.

 

[Computer Nerd Kev]

Wayne Chirnside <frank@fuax.com> wrote:

What they care about is smooth power, no ripple.
Then the thermostat is just a switch not caring what it is attached to as
long as the relay amperage does not get exceeded.

just set an appropriate hystersis.

I thought the aim was for a comstantly variable voltage to control the
temperature, and to avoid a switched action. That's how proper peltier
controllers seem to work.

Additionally, heating will be required if the aim is to keep the container
within the required temperature range over a wide range of ambient
temperature variation.

--
__ __
#_ < |\| |< _#

 

[F Murtz]

Computer Nerd Kev wrote:

Wayne Chirnside <frank@fuax.com> wrote:

What they care about is smooth power, no ripple.
Then the thermostat is just a switch not caring what it is attached to as
long as the relay amperage does not get exceeded.

just set an appropriate hystersis.

I thought the aim was for a comstantly variable voltage to control the
temperature, and to avoid a switched action. That's how proper peltier
controllers seem to work.

Additionally, heating will be required if the aim is to keep the container
within the required temperature range over a wide range of ambient
temperature variation.

In this particular case lower temps are not as much a worry unless very
cold.(keeping chocolate)

 

[Wayne Chirnside]

On Thu, 24 Dec 2015 21:53:00 +0000, Computer Nerd Kev wrote:

Wayne Chirnside <frank@fuax.com> wrote:

What they care about is smooth power, no ripple.
Then the thermostat is just a switch not caring what it is attached to
as long as the relay amperage does not get exceeded.

just set an appropriate hystersis.

I thought the aim was for a comstantly variable voltage to control the
temperature, and to avoid a switched action. That's how proper peltier
controllers seem to work.

Additionally, heating will be required if the aim is to keep the
container within the required temperature range over a wide range of
ambient temperature variation.

On - off works just fine for this application.

Now if heating *and* cooling are required you just flip the polarity of
the peltier.

 

[Chris Jones]

On 25/12/2015 12:11, Wayne Chirnside wrote:
[...]
> On - off works just fine for this application.

I wouldn't dispute that it works well, but you might find that with
on-off control, the peltier devices don't last as long as with
continuous current that varies only slowly (especially for large peltier
devices and high currents). When the current is switched on and off,
there is slight expansion and contraction of the ceramic plates, which
could fatigue the semiconductor pillars within the peltier device
eventually. At least some peltier device manufacturers recommend against
on-off control. If you never experience failures than don't worry about it.

If you care about the input power requirement at less than full output
then there can also be a very slight efficiency advantage with variable
current rather than on-off, provided a very efficient switched-mode
controller is used (with filter inductors and capacitors so that pure DC
comes out). The efficiency advantage is because there are resistive
losses inside the peltier device, which are proportional to I squared
times R, and that works out to be more losses on average for e.g. 20
Amps at 50% duty cycle than it is for 10 Amps at 100% duty cycle. It
won't make any difference to the maximum cooling capability since even
with on-off control that will produce 100% duty cycle, which is the same
as you would get with variable current control.

Chris