--- In Electronics_101@yahoogroups.com
, "advplc" <advplc@...> wrote:
>Trent......It will be field use and I think I've solved the heat
problem by only requiring the heat temp to be insignificantly above
that of the water being tested evan if that temp varies by =/-20F.
I have to flesh out the total ckt with some test set-ups and lab and
hopefully a supplier can help me with what I need in way of
recommendations for components. It will be operating in the low DC
Just in the 2 days I've been here I made a quantum leap in this
project. It's hard to sit here , not talking tto anyone and be able to
keep forging ahead.
Dan-----I occasionally hit a site with usefull info and some ckts or
is there more here than that in cyber-space? doctronics is one that
helped , are most of them linked to a manufacturer?
Thanks to all and I'll be back when I figure out the right ? .
> Is this water purified? Conductivity might be a lot easier to
> monitor than temperature. It eliminates the need to maintain a heat
> controlled environment (which itself might cause convection to the
> flowing water). Is this a fixed test station for checking
> manufactured parts or a device that will be field installed in
> sensitive locations?
> --- In Electronics_101@yahoogroups.com, "Arthur Nicholas Davison"
> <gottanew1@> wrote:
> > --- In Electronics_101@yahoogroups.com, John Popelish <jpopelish@>
> > wrote:
> > >
> > > Arthur Nicholas Davison wrote:
> > > (snip)
> > > > I will be working with well and street / municipal supply so
> > > > range is 40-70 F. For my purpose I'll need to react to an
> > > > decrease in temp to have my device be viable so I'm looking at a
> > o.o1%
> > > > or less range.
> > > > I'm not sure about not needing a separate heater or will a
> > > > thermistor provide enough heat at 9-12V with a current limiter?
> > >
> > > Normally, thermistors used for accurate temperature
> > > measurement are not also used as heating elements, but as
> > > signal devices that provide input to a temperature control
> > > circuit with heating element.
> > >
> > > By the way, nothing measures temperature with instant
> > > reaction. That is with the definition of "instant" being
> > > zero time. Please think about what is a reasonable response
> > > time. A minute, a second, a millisecond a nanosecond?
> > >
> > > Is the point of this exercise to provide a variable out flow
> > > of water with a fixed temperature?
> > >
> > Thanks john,
> > What I'm trying to do is detect a leak in a water supply system by
> > initiating an artificial environment and sensing when "cooler
> > introduced sending a signal be it I or V .
> > I've developed a few chamber designs to aide the expected result.
> > My design criteria is operate at 9-12 volts dc and respond asap
> > will have to be determined in a lab situation testing various
> > materials, ckt configurations,physical design layout ......all that
> > good stuff.
> > Art