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Old 10-15-2008, 11:32 PM   #9 (permalink)
trebuchet03
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Join Date: Dec 2007
Location: Bay Area
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The Miata - '01 Mazda MX-5 Miata
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Quote:
Originally Posted by NiHaoMike View Post
The A/C compressor doesn't use that much power anyways. One datasheet (Danfoss BD250GH) referenced 230W at maximum capacity.
That model is only rated for a max charge of 300g.... I drive a midsize classed car (2000 Jetta), which is spec'd for a charge of 700g + 50g

Danfoss doesn't make a 750g model, but it does make a 800g max model... Which, under max load, draws 660W @24VDC

Now, 27.5 amps might not be too much compared to the KW the engine is putting out in total.... But, even daytime running lights (<55W per light) have an impact on FE. That and, I for one, see a drop in instant FE when I turn the a/c on....

Here's the data sheet on the bd350/350gh dual compressor
http://rc.danfoss.com/TechnicalInfo/..._ed100p202.pdf


That said, it would be cool to switch over to an electric compressor - there's some cool tricks you can do when you have finer control. I'd probably add a bigger accumulator, pwm the motor (as you mentioned) and move some componentry out of the engine bay Not to mention the option for a pre cooling cycle before getting into a car that has been well baked in Florida sun


EDIT
And to answer the thread....
Probably not given the current region I'm living in.... I wouldn't do this without installing an alternative cooling solution first.
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