Rockwell Automation 1788-FFCT NI-FBUS Configurator User Manual - Manual (Page 78)

Publication 1788-UM052B-EN-P - April 2002
G-2
function block A named block consisting of one or more input, output, and
contained parameters. The block performs some control function
as its algorithm. Function blocks are the core components you
control a system with. The Fieldbus Foundation defines standard
sets of function blocks. There are ten function blocks for the most
basic control and I/O functions.
function block a fieldbus application that you create using F OUNDATION Fieldbus
application
IEC International Electrotechnical Commission. A technical standards
committee which is at the same level as the ISO.
input parameter a block parameter that receives data from another block
ISA International Society for Measurement and Control
LAS see Link Active Scheduler
link a group of fieldbus devices connected across a single wire pair
with no intervening bridges
Link Active Schedule a schedule of times in the macrocycle when devices must publish
their output values on the fieldbus
Link Active A device that is responsible for keeping a link operational. The
LAS
Scheduler executes the link schedule, circulates tokens, distributes time and
probes for new devices.
Link master device a device that is capable of becoming the LAS
linkage a connection between function blocks
loop see control loop
m Prefix meaning milli- and has a value of 10 -3
macrocycle the least common multiple of all the loop times on a given link
ML Manual Loader
OD object dictionary
OOS out of service
output parameter a block parameter that sends data to another block
PD Proportional Derivative
PID Proportional Integral Derivative
RC Ratio Control
s seconds
Term Definition