Announcement

Collapse
No announcement yet.

Calibration performed for NTC probe w/ Phidgets

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • Calibration performed for NTC probe w/ Phidgets

    So, I calibrated a NTC probe:

    -- AVX Type NI24 --

    with a 463 ohm resistor, in a voltage divider arrangement.

    From 35 Degrees F to 190 Degrees F.

    I can say with 95% confidence that the following curve fit equation is accurate to +/- 1 degree from 35 degrees to 190. In some cases it is better than .3 degrees F accurate.


    N = -1.4618 * N ^ 6 + 21.062 * N ^ 5 - 127.38 * N ^ 4 + 409.96 * N ^ 3 - 731.9 * N ^ 2 + 626.52 * N + 10.658

    Where N is the phidgets sensor raw value.

    I've incorporated this logic into the latest revision of the RR source code.

    PM me if you need some of the thermisters, they're more accurate and cheaper than the phidgets variety.

    http://i2.ebayimg.com/04/i/06/ff/90/56_1.JPG

    Compare to Phidgets, which has an accuracy of +/- 4 degrees F, and are mounted on a board....these thermisters can be epoxied to anything.

  • #2
    Great work, good find.
    RideRunner...The #1 FE, PERIOD.

    Current Project: DFXVoice [v1.0 Released]
    Next in line: RRMedia v2.0

    DFX 5.1.1 Skin
    Appstore Link

    My RideRunner Plugins
    RRMedia
    RRExtended
    DFXVoice

    "There are no bugs - only undocumented features."

    Comment


    • #3
      Originally posted by greenman100 View Post
      From 35 Degrees F to 190 Degrees F..
      35???
      HARDWARE: Fujitsu Stylistic ST5111w/WiFi and dock, internal Hitachi 500G HD, external 1TB HD, Sierra Wireless Aircard 550, DVD-RW, BoomzBox HD radio, XM Commander, Delorme GPS, Saitek X-52 Pro joystick, BluSoleil Bluetooth, TPMS, FB, Elm327

      Comment


      • #4
        Originally posted by GizmoQ View Post
        35???
        yes, I calibrated them in a variable temperature water bath. Below 35 and I risked freezing, and I didn't seen a need to go above 190. They'll work below 35, just not be as accurate.

        Comment


        • #5
          care to share the code ? If I can merge it the main sources, you won't have to add it when new releases come in. Just email it to me (my email is on my public profile).
          Ride Runner RR's Myspace

          "Being happy is not about having what you want, it's about wanting what you have."
          "The best things in life are always free - but that doesn't mean money can't buy you good things."

          Comment


          • #6
            Originally posted by guino View Post
            care to share the code ? If I can merge it the main sources, you won't have to add it when new releases come in. Just email it to me (my email is on my public profile).
            by now, between this and the other thread, there is sooo much. I think I commented it all, but I'm not sure. I had to modify frmLoader, frmSkin, and modRoadRunner. Is that ok?

            Comment

            Working...
            X