DCA
Level 2,3,4 - ANS-consists of plant supervisory being the main focus.
empowers operators to interact with the DCS using video display units.
monitoring and recording of critical data. completes complex calculations and critical
logic operations beyond the capabilities of the lower systems
command words - ANS-are used to perform a specific operation
data words - ANS-are used to transmit data from the database memory location of a
unit on the data highway
data highway - ANS-it's a communication link between the operator interface and the
controllers
it allows communication and data exchange between all devices for the DCS network
they run in pairs of coaxial cable allowing one cable to be running and one to be a back
up
data redundancy - ANS-any data corruption that is detected will cause an immediate
switch to the back up cable
communication controller - ANS-it manages the communication between highways input
and output units
batch sequencing unit - ANS-deals with external events and internal logic algorithms
Data Aquisition System - ANS-2-16 times as many analogue input and output channels
than the LCU
digital and analogue I/O can be handled
no control functions
LCU - ANS-can be placed near field devices or where the field devices are linked to
communication link
Level 2,3,4 - ANS-consists of plant supervisory being the main focus.
empowers operators to interact with the DCS using video display units.
monitoring and recording of critical data. completes complex calculations and critical
logic operations beyond the capabilities of the lower systems
command words - ANS-are used to perform a specific operation
data words - ANS-are used to transmit data from the database memory location of a
unit on the data highway
data highway - ANS-it's a communication link between the operator interface and the
controllers
it allows communication and data exchange between all devices for the DCS network
they run in pairs of coaxial cable allowing one cable to be running and one to be a back
up
data redundancy - ANS-any data corruption that is detected will cause an immediate
switch to the back up cable
communication controller - ANS-it manages the communication between highways input
and output units
batch sequencing unit - ANS-deals with external events and internal logic algorithms
Data Aquisition System - ANS-2-16 times as many analogue input and output channels
than the LCU
digital and analogue I/O can be handled
no control functions
LCU - ANS-can be placed near field devices or where the field devices are linked to
communication link
