[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]

Re: [T3] gas gauge in 12v conversion?


> 12V. Maybe a series resistor would do it.

	I was wondering about that.

	I opened up a 12v gauge and a 6v gauge tonight.  The 12v gauge has
an internal resistor labelled as 68kOhms, and measures as 71k.  (This is
o.k. to measure -- one end of the resistor is connected to the + input of
the gauge, so I don't have some other current path in parallel to reduce
the apparent resistance of this component.)

	The 6v gauge's internal resistor appears to be unlabelled, but
measures at 28kOhms.

	Half the voltage, ~half the resistance, same current.

	One thing, though -- the 12v gauge has a little coil of windings
of fine wire in its circuit -- it's outside of the heart of the gauge, the
magnets/coil(s) on which the needle rides.  It shouldn't have any direct
effect on the magnetic action that drives the needle.  I can't imagine
that it's significantly resistive.  What would an inductor do in this
simple circuit?

	I'll have to look more closely at the gauge in good light to
determine whether this extra coil in the 12v gauge is simply one of
several components in series, or whether it's slightly more complicated
than that.

-Greg

-------------------------------------------------------------------
Search old messages on the Web!  Visit http://www.vwtype3.org/list/


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]