1.1 Flowsheet Symbols and P&I Diagrams 23

In Table 1.1s, contacts shall be shown in shelf condition.Rising switch actuator will cause contacts to switch.

Multipoint, Multifunction, and Multivariable Devices and Loops

Multipoint devices are indicators or recorders that may besingle or multivariable and receive input signals from two ormore primary elements or transmitters.

Multivariable devices are indicators, recorders, and con-trollers that receive input signals from two or more primaryelements or transmitters and control one manipulated variable.

Multifunction devices are controllers or switches thatreceive input signals from two or more primary elements ortransmitters and control two or more manipulated variables.

Single variable or multivariable multipoint indicators andrecorders for two or three points shall be drawn with bubbleseithera) Tangent to each other in the same order, left to right,

as the pen or pointer assignments:

FIG. 1.1lLow voltage motor control on DeviceNet (detail and P&ID mark up).

HS80001MCC

XGM

81001

STARTP.B.

M

XL

81001

XA

81001

XCR

81001

Ixxx

H/O/A

DETAIL # MLV-01

XSR

81001

L/R Status CommonTroubleAlarm

Start/StopCommand

RunStatus

HS80001MCC

XGM

81001

M

H/O/A

P&ID MARK UP

Ixxx

XCRXSRXLXA

FIG. 1.1mVFD motor control on DeviceNet (detail and P&ID mark up).

MCC

XGM

81001

M

XA

81001

Ixxx

SC

81001

SI

81001

DCS

ENABLE

XSR

81001

XCR

81001

XL

81001

Available

NotAvailable

DCSControl

CommonTroubleAlarm

Start/StopCommand

RunStatus

DETAIL # VFD-01

P&ID MARK UP

MCC

XGM

81001

M

Ixxx

XCRXSRXAXL

SC

81001

VFD

PR∗01

FT∗01

FR∗01

TT∗01

TR∗01

PT∗01

© 2003 by Béla Lipták