Since I have an analog ammeter in the system, one that responds fairly
quickly, I can say that if there is a current spike on startup, it is
neither very large nor very long. It just smoothly swings up to running
current with no overshoot. Running current is dead steady. Startup
current there may be, but it's insignificant when integrated into the
whole shebang.

Mike S also brings up the duty cycle thing.

I tell ya, interpreting specs can be a challenge. Heck, just reading the
darn spec sheet is apparently more than I can handle!

I have no numbers to back me up, not having the van equipped with
telemetry and a data logging system, but my seat o' the pants feeling is
that the Norcold is more efficient in terms of power consumption than
the Vitrifrigo. This based on two to three years of operation of both
refrigerators.

But and all, depending on ambient temp, I find the battery depleted in
the morning somewhere between 28 A/h (80F nights, control set to 7 o'
clock [Mrs Squirrel's frozen drinks]) and 11 A/h (32F nights, control
set to 6 o' clock, a Mrs Squirrel-less trip).

I like the Vitrofrigo's larger capacity and that is operates more
quietly than my Norcold did (YMMV).

--
Jack "Rocket j Squirrel" Elliott
Bend, Ore.
1984 Westfalia. A poor but proud people.
1971 "Ladybug"-brand utility trailer ca. 1972 from a defunct company in
San Clemente, Calif., now repurposed as The Westrailia.

Sent from my kitchen.

On 09/20/2011 03:05 PM, Ian Allan wrote:
> I have seen current draw claims, particularly in marine electronic
> devices such as autopilots and refrigeration systems that are based on
> duty cycle assumptions. For example a 4 amp draw with a 75% duty cycle
> becomes a 3 amp. (average) draw if measured over an hour or some
> protracted length of time. Also in the case of refrigeration I think
> that the start-up current will always be higher that the run current.
>
> Rocket, did you see that? A Therapist!
> :-)
>
> Ian Allan
>
> 86 Syncro
> 85 Westfalia/Bostig
> 84 Westfalia
> 02 Jetta 1.8t