Standard temp and standard pressure

Dear all,

I have ultrasonic metering station consists of ultrasonic flowmeter,700xa gc and flowcomputer floboss 600+.

The standard value of temp. is 60F (15.6 C) but the existing is 15 C so i want to change it at flowcomputer and at Gc.if this applicable,can tou give me the steps.

Note: i want to do the same thing at pressure also...

13 Replies

  • In reply to MOH:

    Firstly i have volume flowmeter and i can change the values at flowcomputer.
    Is it a must to change it at gc
  • In reply to hashem ali:

    And if it must,how to change it on out existing gc (700xa)
  • In reply to hashem ali:

    Hello , thanks for your patience as our experts prepare for and to travel to Emerson Exchange 2016 in Austin next week. I have reached out the (Missing Group) team and heard back that they will have someone address your inquiries when they are back online early next week.

    Best Regards,

    Rachelle McWright: Business Development Manager, Dynamic Simulation: U.S. Gulf Coast

  • For the 700XA, what calculations are you using? GPA, ISO or Both? Settings can be changed through MON2020 or using the LOI if your GC has one. GPA default temperature is 60F while 15C is one of the ISO default temperatures. To determine which calculation you are using, open MON2020 and log into the GC of interest. Click on "Application" on the menu bar. Then click on "Calculations". Then click on "Configuration". What is selected as the Calculation Method? You will want "GPA" or "Both". If you select "GPA", 60F will be the default temperature. To change the pressure, click on "Application" on the menu bar, thne click on "Streams". You can change the pressure on individual streams. For GPA, the default pressure is 14.73. You can override this or you can add up to 3 additional pressures to perform your calculations at. Additional details can be found in the MON2020 manual - www2.emersonprocess.com/.../GC_Manual_3-9000-745_MON2020.pdf.
  • In reply to Bonnie Crossland:

    We use iso calculations.for changing temp. Value fron config under GPA selection,it gives me fixed selection values..So what can i do???
  • In reply to hashem ali:

    if there is any reply for my comments
  • In reply to hashem ali:

    Hello Hashem - I thought I responded but apparently I forgot to hit reply. If you send me your email address, I can send you screen shots to walk you through the process. Select "GPA" as the calculation method under Applications - Calculations -Configuration. While on that screen, you will select units for your measurements. By default, the GPA temperature is 60F and the pressure is 14.73. You can change/add pressure by clicking on Application on the menu bar, then clicking on Streams. You can change the pressure on individual streams (boxes are white). Now if you want use the GPA 60F temperature and custom pressures and still get ISO reports, click on Application-Calculations-Control. You will see a long list of all possible reports. Select the ISO reports of interest. While you are able to customize your pressure values, your temperature values are limited to either the GPA value (60 F) or ISO values (0,15, 20, 25 C).
  • In reply to Bonnie Crossland:

    my mail is eng.hashemali@yahoo.com,and i have another question "if i change this value at GC,i must change it at flowcomputer or not."
  • In reply to hashem ali:

    i want to know what is the change that happened to calculations if i change from"ISO" calculations to "GPA with ISO" calculations except that the temp changed to 60 F.If the temp is the only change,this is better for me to reach my point...please reply
  • In reply to hashem ali:

    Hasham,

    The ISO calculations are performed using the ISO 6976 standard, and the GPA calculations are performed using the GPA 2172 report and the GPA 2145 Table of Physical constants.  There are significant differences in the way the calculations are done, and will generate different values for the same composition.

    It is important that the calculations that you use are consistent across the whole system (GC, Flow Computer) so that you do not create confusion because of the different results.

    Which calculations you use depend on the contract that you have for the sale of the gas. This contract will define the calculations to be used, and the standard conditions for the calculations. Before making any changes in the GC or Flow Computer, it is very important that both parties of the contract (the buyer and the seller of the gas) agree to the changes, and that the changes are made at a specific time and date agreed to by all parties. changing the way the calculations are performed with the agreement of all parties is a very quick way to end up in a legal dispute.

    GPA calculations use a fixed base temperature of 60DegF, and allow for different base pressures (often 14.65PSIA, 14.73PSIA or 15.025 PSIA).

    ISO calucations use a fixed base pressure (101.325 kPaA) and allow for different base temperatures (often 0 DegC, 15 DegC, 15.56 DegC [60 DegF]).

    Generally the base pressures and temperatures will be set up during commissioning, and will not be changed for the life of the metering system, unless there is a renegotiation of the custody transfer contracts.

    Regards,

    Shane

    Shane Hale | Global Business Development Director - Rosemount Wireless | Emerson Automation Solutions

    shane.hale@emerson.com | T +1 952 204 4737 | M +1 713 447 2839

  • In reply to Shane Hale:

    thanks for your effort...