Hello,
Just learning some basics of DeltaV and have a 2 part question:
In a control studio module we are working with a PID block whose PV_SCALE is ranged from 0 to 36 cc/min. We want to change this range to 0 to 96 cc/min, yet each time we change the range we only seem to modify the 'default' value in the parameters while the 'on line' value remains 0 - 36 cc/min. Why is the change not reflected in the PID block?
Secondly, will the range change be captured on the associated faceplate as well or will I need to modify the faceplate somewhere else?
Any assistance, direction or comments would be greatly appreciated.
Cheers!
Make sure to download the control module after you change the values while in configure mode (make sure to check with operations before you download). Once downloaded the change should be refleced in your PID block online and the associated faceplate should update automatically.
In reply to tklatt:
In addition to these forums, there are several other very good resources for building a foundation of your understanding of DeltaV:
1. Attend the introductory DeltaV courses provided by Emerson and their business partners
2. Read Books On Line, available on every DeltaV system.
3. Get familiarity with a DeltaV simulation system before working with a production system.
Like with any process control system, a fundamental understanding of the architecture and technology is key.
Good luck!
In reply to Youssef.El-Bahtimy:
Hello and thanks for the information ... I need to clarify a few items:
The PV_SCALE from the PID block is 0 - 36cc/min and this value is then entered into the OUT_SCALE of a SCLR block. The OUT of the SCLR block is then entered back into the PID block IN as feedback.
I have successfully changed PV-SCALES on other modules and seen the changes reflected on the faceplate, but this current module will not let me adjust the PV-SCALE.
When I am on-line with the module and select the PID block and look at the parameter column I see the on-line value is 0 - 36 cc/min and the default value is 0 - 96 cc/min. I cannot seem to over-write the 0 - 36 cc/min value.
Is there something special with the relationship of the PID block and the SCLR blocK?
Any ideas?
In reply to cwicz77:
So I have built what you described-
1. PID/PV_SCALE feeds into SCLR/OUT_SCALE
2. SCLR/OUT feeds in to PID/IN.
I have started with a PID/PV_SCALE of 0-33 whatever, downloaded and can see that as the scale through control studio online.
I then changed the database value for PID/PV_SCALE to 0-96 whatever, downloaded and can see the updated value on line.
The only reason I could think for a PID to not accept a changed PV_SCALE is if the PID block is tied to a fieldbus device which is dictating the scale. Can you confirm whether you are using a fieldbus shadow PID block?
Can you change the PV_SCALE value online? You will need to set the PID to OOS mode first, but you should be able to change the scale online for immediate results (again unless it is a fieldbus block).
In reply to AdrianOffield:
Hi,
If default range is showing desired value, then it seems the download is done correctly.
Are you sure some other logic is not writting the PV_SCALE online on the PID block?
Can you please provide the snapshot of the module online, with property window indicating the PID parameters?
Regards,
Amod.
Phone: 7575385032, Mobile: 7574351909, Fax: 7575385026, E-Mail: Stuart.Greenhalgh@basf.com Postal Address: 2301 Wilroy Road, Suffolk, Virginia USA, 23430
BASF - The Chemical Company From: "cwicz77" <bounce-cwicz77@community.emerson.com> To: <DeltaV@community.emerson.com> Date: 09/23/2013 02:48 PM Subject: [EE365 DeltaV Track] DeltaV control studio/faceplate basics