Daryo May 22, 2012:

double (caractéristique à préciser)? "dual rate" applies for sure to the "generator" ("turbine" is just what is driving the generator).
From I could find "dual rate" applies to some of the specs of that generator.
I just mentioned the most likely "candidates" for being "dual rated" (i.e. voltage or frequency of the generated AC current).
A very high-power generator permanently connected to the "réseau de haute tension" must always generate the same voltage and frequency, so it would have to be "dual rated" for something else.
Take a look at
http://french.alibaba.com/products/hydro-turbine-generator.h...
it might give you some clues?
BTW, here is a "DUAL RATED TURBINE GENERATOR" of low power (just for one household!) that is dual rated for voltage:
http://french.alibaba.com/product-gs/10kw-micro-hydro-turbin...
I think "dual rated" is not specific enough. From the context it must be clarified if it's "double tension" "double frequence" "double norme" or something else. Very frustrating when authors omit what's obvious to them!

florence metzger May 21, 2012:

c'est un alternateur entrainé par une turbine donc une grosse puissance et je n'ai jamais vu un alternateur de ce type de puissance pouvant avoir deux tensions de sortie.. je pense que dual rate s'applique à turbine..

Daryo May 21, 2012:

dual rated for voltage=Générateur double tension this generator could be
-- dual rated for voltage - capable of generating either 110V or 220/240V, so it could be used on building sites (110V in UK) and for general use (240v)
or
-- dual rated for frequency - can be set to generating 50Hz (for Europe) or 60 Hz (for USA) output so it can be sold worldwide
as in : “The generator is available in an air-cooled or TWAC configuration and is dual rated (50 and 60 Hz)” ref: https://www.epelectric.com/document/nmprc-case-12-00137-ut-0...

A possible translation:
“Générateur double tension” if it’s dual rated for voltage ref http://radiospares-fr.rs-online.com/web/p/generateurs-portab...

Bridget Jean (asker) May 20, 2012:

Hi Tony! Many thanks for your comments and advice.
I have searched before asking the question but I didn't find anything.
The problem is that I only have diagrams without any context and absolutely no idea of what it is for.
So maybe it's better that my colleagues don't waste their precious time on this subject...

Tony M May 20, 2012:

Context? We've had this term before, and in certain contexts it has a quite specific meaning; we need to know as much more information as you have about this t-g, and especially, if it seems to be being rated by somebody or other?

I strongly recommend you to check out the previous entry (use a 'term search' to see if the answers given there fit your context.