Date:         Mon, 6 Sep 2004 15:04:00 -0700
Reply-To:     Rocket J Squirrel <j.michael.elliott@ADELPHIA.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Rocket J Squirrel <j.michael.elliott@ADELPHIA.NET>
Subject:      Re: 12v Aftermarket Coolers ? Any Good?
Comments: To: Vince S <gipsyflies@COMCAST.NET>
In-Reply-To:  <000d01c49454$0b2ba570$c200a8c0@vsovaio>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Vince S wrote:

>Sorry I meant Danfoss from Denmark. Coolmatic is one cooler with these
>compressor. There may be other cooler with other compressors that may be
>cheaper.
>
>http://www.waeco.com/pages/products/mk/cmkbov_truck_d.htm
>
>
>
Hmmm . . . I'm wanting to learn how to translate deep cycle battery
ampere-hour ratings into real world performance, and these reefers seem
like a good exercise.

Assume we are using a fully-charged deep-cycle battery, like an Optima,
rated at 52Ah (C/2) / 65Ah (C/20) to run the reefer.  Also assume its a
hot day, 32C. Finally, assume that there is some nicely chilled lager in
the reefer that we would hate to see get warm. Here are the data for two
of the Danfoss reefers:

Danfoss CDF-35 "incredibly inexpensive" 31 liter model.  It is rated at
45 watts, and has an average running time:  of 30% at 32C ambient
temperature. Its rated power consumption is defined as power input x
average running time. For this model, then, we are talking 30% of 45W,
or 13.5W ~ 1Ah.

Danfoss  CF-25 (not-so-incredibly-inexpensive) -- their smallest model.
25 liters, average power consumption:   35 watts, average running time:
19% at 32C ambient temperature. This translates to 6.7W, ~560mA.

For these two models, then, how long before the compressor stops chugging?
--

Mike "Rocket J Squirrel" Elliott
71 VW Type 2 / 84 Westy: A poor but proud race.
KG6RCR