310204a Drawings And Symbols Flashcards
Describe this signal type
Instrument connections to process and equipment, process impulse lines and analyzer sample lines
Describe this signal type
Electronic or electrical continuously variable or binary signal, functional diagram binary signal
Describe this signal type
Pneumatic signal, continuously variable or binary
Describe this signal type
Communication link or bus, connecting 2 or more independent microprocessor or computer-based systems.
Describe this signal type
Filled thermal element capillary tube, filled sensing line between pressure seal and instrument.
Describe this signal type
Hydraulic signal
List the 5 main failure modes for control valves.
- Fail open
- Fail closed
- Fail locked in the last position
- Fail in last position drift open
- Fail in last position, drift closed
List the two common continuously variable or binary signal symbols
- Electronic or electrical, continuously variable or binary signal functional diagram binary signal
- Pneumatic signal continuously variable or binary
What are the main uses for P&IDs?
- For operational method
- To develop safety and safeguards
- To help design and comprehend control basics and philosophy
- For troubleshooting
List the three most common documents that production facilities use
- Process flow diagram (PFD)
- Process and instrumentation diagram (P&ID)
- Instrument loop diagram (ILD)
Define a discrete instrument
A discrete instrument is one that stands alone
Explain the customary application for SAMA diagrams
SAMA diagrams is for boiler control logic graphical representation
Explain the difference in the way that SAMA represents the process when you compare them to P&IDs
The difference between SAMA and P&IDs is in the flow of information. While SAMA shows the flow of information from the top (field) to the bottom (burner) P&IDs generally flow from left to right across the page and are more representative of the interconnection of the various equipment and instrumentation.
Why would you need to draw a PFD or a P&ID?
In the field, you may not have access to the drawings, so you would need to draw a representation of the process to help understand, and describe the process or problem to someone else.
What does an ISA bubble with a line through it in a square mean?
This circle represents the discrete instrument, the solid line represents the main control room, and the square depicts the location of the device in a shared display.
