P&ID drawing pump, valves, flowmeter, etc reference

Hello all,

Im currently working on building a SCADA system. The customter has provided me with the P&ID drawings. Their are a lot of valves, pumps, flow meters, flow switches etc. I have highlighted some examples below

Temperature controlled valve 15 is labeled as TCV
Pressure reading are labled as PIT
High limit switches are labeled as LSH
Temperature reading are labled as TIT
Digital on/off valves are labaled as XV1
open/closed valve limit switches are labeled as ZSC and ZSO

so my question is some of these references i can't tell just by looking at it, and although i could ask the customer, i wanted to know if you guys have any references you use when you want to look up what each abbreviation stands for??

It's ISA coding used in process instrumentation.
You can find more info on that for example here:
http://www.engineeringtoolbox.com/isa-intrumentation-codes-d_415.html

yeah i did a google search and found numerous links, i was looking to get opinions on everyone here and what they found to be useful

This is my source:
http://www.everyspec.com/search_res...php&ref=www.everyspec.com/&ss=6292j2241490j21

vol1 and vol2 of "engineering symbology"

Typically P&IDs are issued with a legend as the one of the first pages. The legend will show valve types, pumps, etc along with the instrument symbols and abbreviations and such. I would like to think that the P&ID designers would have included this type of reference. No dice??

Probably wouldn't hurt to ask.

ISA is probably (one of) the most comprehensive resource for this type of information. They have a published standard "ISA-5.0-1984(R1992) Instrumentation Symbols & Identification" that will tell you more bout this than you ever want to know. Unfortunately, they charge you for it, but it is a resource that is invaluable to anyone who works with P&ID control drawings, IMHO. You can find more information here: http://www.isa.org .

These designators pretty much tell their own story a lot of the time:

PI = Pressure Indicator
PIT = Pressure Indicating Transmitter
TIT = Temperature Indicating Transmitter
LCV = Level Control Valve

Where it gets fuzzy is when some of the modifiers are used. If you use them often, it becomes second nature.

As I said, the ISA comes in very handy.

Paully's5.0 said:

Typically P&IDs are issued with a legend as the one of the first pages. The legend will show valve types, pumps, etc along with the instrument symbols and abbreviations and such. I would like to think that the P&ID designers would have included this type of reference. No dice??

Probably wouldn't hurt to ask.

Click to expand...

+1 for this. The designers probably included their key with the overall package but whoever forwarded the drawings to you probably didn't realize that you may need these normally pro forma sheets. I would recommend you get the correct one for the project you are working on in case that someone deviated from the ISA standard symbols or terminology (not that anything like that ever happens in real world projects)

The Wikipedia article isn't too bad:
http://en.wikipedia.org/wiki/Process_and_instrumentation_diagram

+1 Tom... I didn't know that someone had extracted the table from the ISA standard (that I paid for!) and posted it on Wikipedia. The rest of the document is missing, but the table gives you the meat of things.