×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

rosemount 3144 Temp transmitter question

rosemount 3144 Temp transmitter question

rosemount 3144 Temp transmitter question

(OP)
I have a 3144P, 0-150deg F, 4-20ma output.   Using a test device to simulate RTD input to the transmitter, I have 0F and 4ma output and at 150F i have 20ma output and it is read correctly on my PLC.  This is all good, the problem lies with this, when I put a calibrated temp probe in the thermowell next to the transmitter to verify the temp my test probe reads 1.2 degrees more than the transmitter.  I need to calibrate the transmitter or adjust the transmitter to read the correct temperature as the test probe, within .5 degrees.  I have not done this in a while so am rusty at this, need a refresher.  Is the RTD bad?
Thanks.

RE: rosemount 3144 Temp transmitter question

The Sensor Trim command allows the user to digitally alter the transmitter's interpretation of the input signal as shown in Figure 3-6 on page 3-28. The sensor trim command trims, in engineering (°F, °C, °R, K) or raw (Ω, mV)units, the combined sensor and transmitter system to a site standard using a
known temperature source.

pg 60, Rosemount 3144P Temperature Transmitter manual
http://www2.emersonprocess.com/siteadmincenter/PM%20Rosemount%20Documents/00809-0100-4021.pdf

Navigation sensor trim is 1 > 2 > 2 > 1 > 1 according to the menu structure:

RE: rosemount 3144 Temp transmitter question

As I said on the other site you posted make sure that one of your RTDs is not a different curve.

RE: rosemount 3144 Temp transmitter question

(OP)
Thanks, I can't find the other site I posted on.   Out of town now so will try it out when I get back.  The process is out of service right now so I have time. Thanks

RE: rosemount 3144 Temp transmitter question

Sensor trim.  Nice.  It somehow seems to legitimise the old instrument tech response:  OK, What do you want it to read?

If the rtd is the right animal (and such a small difference suggests it is) you should consider what is different between the reference instrument and this transmitter: length/diameter of t-well vs length/diameter of probe, use of heat paste and then put both of them in ice water and boiling water and use this reference to calibrate the sensor.  RTD's usually read very accurately or not at all.  I would be looking for installation issues here.

RE: rosemount 3144 Temp transmitter question

(OP)
Another question, the manual speaks of upper and lower trim, does this mean 0 and 150f.   Getting confused again.   So do I have to do what the previous post says too?  Basically I want to know how to make it read the same as the test probe, in simple terms.  

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources