Good day support team, many thanks in advance for your valuable feedback. Could you please help me with this technical clarification?
Target: Calibrate Absolute pressure transmitter (Hart) which has a range: 0 - 200 psia (absolute)
I would like to reinforce this point: from the Rosemount manual, a recommendation states: Do not perform a Zero trim on Absolute pressure transmitter (since they are reference to absolute zero, really difficult to reach).
If zero sensor trim is not highly recommended, a Lower sensor trim is an option to be performed. How Can I perform this Lower sensor trim in an absolute pressure transmitter without altering the factory curve?
This transmitter is installed at site which has an atmospheric pressure of 14.69 psig (provided by marine department). In addition to that, we can get the information by using an Absolute pressure module Fluke 700PA6 connected to the Fluke 754. From the Fluke the Atmospheric pressure is 14.74 psig. Considering that the Fluke is more accurate, so the considered atmospheric pressure will be 14.74 psig.
Is it correct to perform the:
Lower sensor trim at 14.74 psig and
Upper sensor trim at (200 -14.74) 185.26 psig
I just wonder if Both sensor trim could affect the curve (since from Factory, the first point was considered the Absolute zero).
Since, I have never done a Lower trim on Absolute pressure transmitter, if the Lower and Upper sensor trim is done, What happens with the initial range which is 0 - 200 psia?
Many thanks for your support and valuable feedback.
Kind regards,
Thales
In reply to Brad Burton: