Re: Conductivity sensors



Why connect the grounds? Even if you have to connect them, use
inductors. The probes seems to be AC shorted.

I have the grounds connected simply because the A/D board is set up as
single-ended, i.e., it's reading each channel relative to common
ground. I can rewire some things to route the ground of each signal
through the multiplexer and run the board in differential mode.

I see what you are saying about AC noise, although I'm new enough at
this that I have a hard time wrapping my brain around AC. Why is it
that the current would drop in a shorted situation? I would have
guessed, though without knowing why, that it would have increased...

Thanks for giving me some things to try.

.

Relevant Pages

  • Re: FW: [SLE] Need help diagnosing hardware problem
    ... On Tuesday 17 October 2006 21:41, Greg Wallace wrote: ... alongside the wire and don't need to unplug anything to get the readings. ... tips on probes, and that can happen. ... how to get reading if surface is dirty without forcing the probe to slip in ...
    (SuSE)
  • Re: Buying second hand!
    ... Take along a damp test meter - Aldi had some digital ones recently ... for £10 - they just need the probes modifying to make them a little ... Won't such modifying affect the reading in some way? ... They simply measure the resistance or conductivity of the material they ...
    (uk.rec.caravanning)
  • Re: Conductivity sensors
    ... inductors. ... The probes seems to be AC shorted. ... For the same reasons as you can turn on one light in your house without ...
    (sci.electronics.design)
  • Re: Digial Voltmeter DC and AC mode
    ... Is it correct to say that if the signal = DC component + AC component then DC reading gives the DC component and AC reading gives the AC component? ... imagine putting this cell on a rotating plate on it's side. ... as the plate turns with the cell lying on it, the - + terminals are getting closer to the probe tips, lets say the meter is reading the approaching terminals of the cell giving you a stronger reading until they are perfectly lined up with the 2 probes! ... now the cell is still turning and as it does the voltage is now going down. ...
    (sci.electronics.basics)
  • Re: Buying second hand!
    ... Take along a damp test meter - Aldi had some digital ones ... Won't such modifying affect the reading in some ... A smaller contact area due to smaller diameter probes will ... Thanks, Harry. ...
    (uk.rec.caravanning)