"Blueskies" wrote in message
. com...

"MikeR" wrote in message
...


No wheel in this one (electrical impulses).



Impulses from what?


Ref: http://203.167.230.122/qiss/scripts/FAQFrame.htm


Title: How does the flow transducer work?
Question/Symptom:
How does the flow transducer work?

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Answer/Solution:
NAVMAN flow transducers are of an optical type. Within the transducer
are a transmitter and receiver that output an infrared beam through the body
of the transducer. Inside the transducer is a very precisely dimensioned
turbine running on jewelled bearings. As the fuel flows it spins the turbine
and the blades cut the infrared beam, which transmits a pulsed signal to the
fuel computer.