In a message dated 24/02/98 18:15:02, aa4bwi@zen.sunderland.ac.uk writes:
<< A repeater for the instument panel , in plain view would be ace ....
any ideas ? >>
There is another type marine gauge I have on a 25ltr tank. This has a float
running up a rod. A coarse fixed helix around it forces it to rotate as it
rises and the rotation is coupled to the pointer of a gauge in the filler cap.
Unfortunately the device works only for the designed depth which in the
version I have is 10 inches. For the Europa you need 15". It would need to be
scaled proportionately in diameter to avoid the helix getting too coarse,
which would stick the float.
This (or the one described by James Nelson, or any other mechanical rotation
for that matter ) can be repeated remotely to a digital or led array
display, by replacing the pointer with an absolute optical encoder disc. This
needs only a few rings ( 4 or 5 bits would be enough, unlike the 10 to 15 of
the expensive commercial devices) and could be designed to allow for the 3
steps in the tank section .
Note though that the PFA do not like rotating or sliding shafts coming out
of fuel tanks because of the possible failure of the seal. Neither do they
like fuel filled instruments glasses (which the helix device has) because of
possible failure in an accident. But you can have the repeater disc in a
metal enclosure. Next discussion - volts in the tank-- again ?
Graham C G-EMIN
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