Temperature depending cooling fan in car

[ytreboe]

I have an old car and I want to install an electric 12V cooling fan instead
of the belt driven.

I would like the fan to vary rpm depending on temperature. (higher temp=
higher rpm.)
Is this diffivult to make? New cars has this type.

I have a 12 V fan from a n old japanese car. What do else I need to make it?

Ps I'm not so much in the electronic business
.
Ingvar
Norway.

 

[bj]

"ytreboe" <ytreboe@online.no> wrote in message
news:K9SJb.362$nJ2.6217@news4.e.nsc.no...

I have an old car and I want to install an electric 12V cooling fan
instead
of the belt driven.

I would like the fan to vary rpm depending on temperature. (higher temp=
higher rpm.)
Is this diffivult to make? New cars has this type.

I have a 12 V fan from a n old japanese car. What do else I need to make
it?

Ps I'm not so much in the electronic business
.
Ingvar
Norway.

Hi
I am not an expert in either electronics or mechanical engineering

but the way I see your problem is this
1) You do not need to vary the fan rpm depending on temperature--- all you
need to do is switch the fan on when the engine is getting too hot----most
of the time when you are just driving along there will be enough air flow
through the radiator to keep the engine happy---and also running a bit more
efficiently because this brainless fan is not running all the time.
2) So now most of your problems are mechanical ones ---apart from getting a
fused 12v feed to the fan
a) Have you got enough room to mount the fan to the radiator? --bearing in
mind that the fan belt was probably driving the water pump as well and you
will have to keep this going all the time
3) The switch that normally turns these fans on in modern cars---either
because you are stuck in a traffic jam , or making the engine work hard ie.
towing someting really heavy--- is usually located at the bottom of the
radiator and you will have to get one of these and somehow plumb it into
your own radiator--or probably the hose leading to it
4)when you are testing all all of this remember that if the engine is
overheating a little bit you can cool it down by turning the heating in the
car onto max and fan on full and open the windows

hope this helps

bj

 

[DaveC]

On Sun, 4 Jan 2004 9:57:43 -0800, bj wrote
(in message <bt9k6v$9cn$1@news7.svr.pol.co.uk&gt:

a) Have you got enough room to mount the fan to the radiator? --bearing in
mind that the fan belt was probably driving the water pump as well and you
will have to keep this going all the time

These electric fans typically mount forward of the radiator -- between it and
the grille.
--
DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group

 

[ytreboe]

"DaveC" <me@privacy.net> wrote in message
news:0001HW.BC1DAA3B001FDF99F0080600@news.individual.net...

On Sun, 4 Jan 2004 9:57:43 -0800, bj wrote
(in message <bt9k6v$9cn$1@news7.svr.pol.co.uk&gt:

a) Have you got enough room to mount the fan to the radiator? --bearing
in
mind that the fan belt was probably driving the water pump as well and
you
will have to keep this going all the time

These electric fans typically mount forward of the radiator -- between it
and
the grille.
--
DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group

The problem is how to vary the speed of the fan. Not the mechanical. On my

former car I built it in the traditional way. With thermostat on/off.
The problem now is to make it like a new Mercedes. The hotter the engine
is,the more rpm on the fan.

 

[the Wiz]

"ytreboe" <ytreboe@online.no> wrote:

"DaveC" <me@privacy.net> wrote in message
news:0001HW.BC1DAA3B001FDF99F0080600@news.individual.net...
On Sun, 4 Jan 2004 9:57:43 -0800, bj wrote
(in message <bt9k6v$9cn$1@news7.svr.pol.co.uk&gt:

a) Have you got enough room to mount the fan to the radiator? --bearing
in
mind that the fan belt was probably driving the water pump as well and
you
will have to keep this going all the time

These electric fans typically mount forward of the radiator -- between it
and
the grille.
--
DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group

The problem is how to vary the speed of the fan. Not the mechanical. On my
former car I built it in the traditional way. With thermostat on/off.
The problem now is to make it like a new Mercedes. The hotter the engine
is,the more rpm on the fan.

If you want more than on/off control, you're looking at much more sophisticated
control system.

The simplest system would be to have multiple thermostats, with the lowest
temperature thermostat provided very reduced power to the fan (just enough
voltage/current to move more air than the vehicle's speed). The next thermostat
would provide more drive to the fan, and the highest temperature thermostat
would provide full voltage to the fan.

Better control will require some electronics. You'll need a microprocessor of
some type to do the following:
1. monitor actual coolant temperature
2. control PWM motor controller to provide full control of fan speed

Since you're building this from scratch, you might want to include a standard
thermostat that switches full voltage to the fan if the electronics fail when
the engine is hot ;-)

More about me: http://www.jecarter.com/
VB3/VB6/C/PowerBasic source code: http://www.jecarter.com/programs.html
Freeware for the Palm with NS Basic source code: http://nsb.jecarter.com
Drivers for Pablo graphics tablet and JamCam cameras: http://home.earthlink.net/~mwbt/
johnecarter at@at mindspring dot.dot com. Fix the obvious to reply by email.

 

[Glenn Gundlach]

"ytreboe" <ytreboe@online.no> wrote in message news:<X%%Jb.487$nJ2.9025@news4.e.nsc.no>...

"DaveC" <me@privacy.net> wrote in message
news:0001HW.BC1DAA3B001FDF99F0080600@news.individual.net...
On Sun, 4 Jan 2004 9:57:43 -0800, bj wrote
(in message <bt9k6v$9cn$1@news7.svr.pol.co.uk&gt:

a) Have you got enough room to mount the fan to the radiator? --bearing
in
mind that the fan belt was probably driving the water pump as well and
you
will have to keep this going all the time

These electric fans typically mount forward of the radiator -- between it
and
the grille.
--
DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group

The problem is how to vary the speed of the fan. Not the mechanical. On my
former car I built it in the traditional way. With thermostat on/off.
The problem now is to make it like a new Mercedes. The hotter the engine
is,the more rpm on the fan.

If you want a Mercedes.....
GG

 

the Wiz <look@message.body> wrote in message news:<rfkhvvgk2pu7vdbd4ihkb33ldorbmll0j5@4ax.com>...

"ytreboe" <ytreboe@online.no> wrote:


"DaveC" <me@privacy.net> wrote in message
news:0001HW.BC1DAA3B001FDF99F0080600@news.individual.net...
On Sun, 4 Jan 2004 9:57:43 -0800, bj wrote
(in message <bt9k6v$9cn$1@news7.svr.pol.co.uk&gt:

a) Have you got enough room to mount the fan to the radiator? --bearing
in
mind that the fan belt was probably driving the water pump as well and
you
will have to keep this going all the time

These electric fans typically mount forward of the radiator -- between it
and
the grille.
--
DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group

The problem is how to vary the speed of the fan. Not the mechanical. On my
former car I built it in the traditional way. With thermostat on/off.
The problem now is to make it like a new Mercedes. The hotter the engine
is,the more rpm on the fan.



If you want more than on/off control, you're looking at much more sophisticated
control system.

The simplest system would be to have multiple thermostats, with the lowest
temperature thermostat provided very reduced power to the fan (just enough
voltage/current to move more air than the vehicle's speed). The next thermostat
would provide more drive to the fan, and the highest temperature thermostat
would provide full voltage to the fan.

Better control will require some electronics. You'll need a microprocessor of
some type to do the following:
1. monitor actual coolant temperature
2. control PWM motor controller to provide full control of fan speed

Since you're building this from scratch, you might want to include a standard
thermostat that switches full voltage to the fan if the electronics fail when
the engine is hot ;-)

More about me: http://www.jecarter.com/
VB3/VB6/C/PowerBasic source code: http://www.jecarter.com/programs.html
Freeware for the Palm with NS Basic source code: http://nsb.jecarter.com
Drivers for Pablo graphics tablet and JamCam cameras: http://home.earthlink.net/~mwbt/
johnecarter at@at mindspring dot.dot com. Fix the obvious to reply by email.

It already exists

www.dccontrol.com