Date: Sun, 25 Apr 2010 12:47:17 -0500
Reply-To: Tom Hargrave <thargrav@HIWAAY.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Tom Hargrave <thargrav@HIWAAY.NET>
Subject: Re: PWM controller ,
was Water Cooler System Design Flaw Workaround?
In-Reply-To: <x2n71d9cdf91004251024l1847eceak3ad3136c44a5273b@mail.gmail.com>
Content-Type: text/plain; charset="us-ascii"
Yep, that works fine as long as you remember to switch it on & back off.
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On Behalf Of
Jake de Villiers
Sent: Sunday, April 25, 2010 12:25 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: PWM controller , was Water Cooler System Design Flaw
Workaround?
Like a manual switch controlled by the most amazing data processor of all,
the human brain? ;)
On Sun, Apr 25, 2010 at 9:06 AM, Tom Hargrave <thargrav@hiwaay.net> wrote:
> I just found the schematic on line and they are already using engine
> temperature to control the fan. I thought they would since VW is a
> excellent company.
>
> This being the case, something may be worth designing that turned on
> the fan earlier based on temperature change, like for example when
> pulling a hill, to give the cooling system a jump start on cooling.
>
> Tom
> www.towercooler.com
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On
> Behalf Of Mike "Rocket J Squirrel"
> Sent: Sunday, April 25, 2010 10:18 AM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: PWM controller , was Water Cooler System Design Flaw
> Workaround?
>
> Alistair Bell wrote:
> > my rad fan is 450 W if that helps
> >
> > alistair
> >
> > PS i dont see the point in a pwm controlled fan, I would concentrate
> > in a more sophisticated temperature interpretation, ie a PID
> > controller... monitor rate of temp change to that fan can keep on
> > top of things...
> >
> > but you know, my experience of the fans in real life is that they
> > come on, cool the van down and go off.... seem to work fine :)
>
> I'm with the Bell on this one. The radiator on the fan is capable of
> creating lots of cool water, and the thermostat opens and closes as
> needed to draw from that reservoir. If the engine was seeing huge over
> and undershoots in temperature then a better control system would be
warranted.
> But the large thermal mass of the engine pretty much assures that temp
> changes will occur pretty slowly, and the thermostat seems capable of
> keeping up with them.
>
> I guess I don't see a problem that needs solving. But I do enjoy fancy
> engineering for engineering's sake, too.
>
>
> --
> Mike "Rocket J Squirrel" Elliott
> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
> 74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.)
> Bend, OR KG6RCR
>
--
Jake
1984 Vanagon GL 1.9 WBX 'The Grey Van'
1986 Westy Weekender/2.5 SOHC Suby 'Dixie'
Crescent Beach, BC
www.thebassspa.com
www.crescentbeachguitar.com
http://subyjake.googlepages.com/mydixiedarlin%27
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