Results 1 to 8 of 8

Thread: thermocouple type?

  1. #1
    Senior Member
    Join Date
    Jan 2008
    Location
    Brisbane, Queensland, Australia, Australia
    Posts
    1,756

    thermocouple type?

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    I was wondering if anyone knew what type of thermocouple the CS probe was, i know its k-type, but is it grounded, ungrounded or exposed(this i doubt)

    As per the pic below, looking for alternatives for the CS DMM and Datalogger software for the behmor bean mass probe ;)


  2. #2
    A_M
    A_M is offline
    Guest
    Join Date
    Mar 2006
    Posts
    6,381

    Re: thermocouple type?

    Quote Originally Posted by 696D4B525257485F503E0 link=1274183007/0#0 date=1274183006
    I was wondering if anyone knew what type of thermocouple the CS probe was, i know its k-type, but is it grounded, ungrounded or exposed(this i doubt)

    As per the pic below, looking for alternatives for the CS DMM and Datalogger software for the behmor bean mass probe ;)
    My gut says option 2 as per ya graphics, if ya talking as per teh following pic. Note a Simple test using ya eyes and teh multi meter will prove ;D


  3. #3
    Senior Member
    Join Date
    Jan 2008
    Location
    Brisbane, Queensland, Australia, Australia
    Posts
    1,756

    Re: thermocouple type?

    I had a laugh, yeah, so im guessing continuity test(simple for laypersons) from outside of probe to any one of the wires year? (to prove grounded or un grounded, if it was grounded, how would this work? - a bead that is terminated on the outer shell of the probe, isnt the temperature worked out on the difference in resistance between two different compounds/materials? wouldnt you be introducing a third with the probe?

  4. #4
    A_M
    A_M is offline
    Guest
    Join Date
    Mar 2006
    Posts
    6,381

    Re: thermocouple type?

    Quote Originally Posted by 696D4B525257485F503E0 link=1274183007/2#2 date=1274220151
    n the difference in resistance between two different compounds/materials?
    No... *The different metals generate a voltage.. *

    This is why many temp meters and probes are so inaccurate etc... *

    The voltages are bloody small; thus impedances and cct stability is so important and that costs money.. The K type and the CS meter as a system have inaccuracies of greater than second crack or 3C...

    The issue is it does not matter as the repeatability is is not quite as bad and then there is what one actually needs..

    The issue is another user attempting to get exactly the same reading... *If ya +/- 3 or ever 5c .. Ya on the money.

    My good meter and probe... Rated and NATA calibrated at 0.5C is one of the cheaper ones but still cost > $700

    The one at work is rated at 0.first crack - *the single function meter is only about $700 but the probes are $1k plus for a limited temp range and their linearity is great.

  5. #5
    Senior Member
    Join Date
    Jan 2008
    Location
    Brisbane, Queensland, Australia, Australia
    Posts
    1,756

    Re: thermocouple type?

    Thanks Mark, just looking for a thinner k-type for the behmor, im aware of the error margin, its all relative hey ;)

    Thanks again
    warren

    PS i have an earache like you wouldnt imagine! :(

  6. #6
    A_M
    A_M is offline
    Guest
    Join Date
    Mar 2006
    Posts
    6,381

    Re: thermocouple type?

    Quote Originally Posted by 63674158585D42555A340 link=1274183007/4#4 date=1274222837
    Thanks Mark, just looking for a thinner k-type for the behmor, im aware of the error margin, its all relative hey ;)

    Thanks again
    warren

    PS i have an earache like you wouldnt imagine! :(
    Now is this a giggled like a schoolgirl as ear ache is caused by future wife OR more serious ?

    My wrist is much better to day.. But that pointy bit on the other elbow is still painful.

    thinner k-type
    The issue here is like our expensive probes super thin for testine very smap sample wells for dna and other testing.. Size. Most what things bigger... But some times smaller is better and has more quality....

    Dissimilar metals, thus they can not touch except at the junction point. Therefore they need to be insulated. Cheep means the insulator material, is usually not rated at high and or prolonged temps.

    How thin do ya want it... Or is it not thick like some ;D


  7. #7
    Senior Member
    Join Date
    Jul 2008
    Location
    Port Fairy
    Posts
    2,993

    Re: thermocouple type?

    I havnt seen the inside of a Behmor but if the drum end is open like the Hottop at one end then fitting a bead type for faster response should be possible.

    I got a bead type from Andy before I got the meter last week and I have bent up a bit of thin brass tube (model aircraft supplies) at 90 degrees to the rear (for the Hottop) wall so that the bead type can be out in the open bean mass but fairly protected mechanically by the tube being in front of it from direct bean hits.

    I will take some pics when it gets fitted up if that doesnt make sense. The plan is to see how the bead goes, if it fails I will go back to the more standard solid probe.

  8. #8
    Junior Member
    Join Date
    Jun 2014
    Location
    N.E Victoria
    Posts
    8
    Behmor Coffee Roaster
    I found this article to be a good read on probes and roasters:- https://www.cropster.com/probe-guide...s-perspective/



Similar Threads

  1. Need help re new thermocouple
    By greencardigan in forum Roasters
    Replies: 18
    Last Post: 13th September 2014, 09:37 PM
  2. Fitting a bead type thermocouple (to a Silvia).
    By Toad in forum Brewing Equipment (non-machine specific)
    Replies: 3
    Last Post: 28th August 2012, 09:18 PM
  3. thermometer with K type thermocouple
    By Gra in forum General Coffee Related...
    Replies: 12
    Last Post: 24th February 2009, 08:13 PM
  4. Ozito heatgun meltdown and Type K thermocouple
    By Intellidepth in forum Home Roasting - Tips, Tricks, Ideas
    Replies: 3
    Last Post: 30th June 2008, 10:25 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •