what is LAS in foundation fieldbus protocol?
Answer / carl_ellis
What is Foundation Fieldbus LAS?
Link Active Scheduler (LAS)
A Link Active Scheduler (LAS) is a deterministic,
centralized bus scheduler that maintains a list of
transmission times for all data buffers in all devices that
need to be cyclically transmitted. Only one Link Master
(LM) device on an H1 fieldbus Link can be functioning as
that link's LAS.
The Master and Primary Backup Link Active Scheduler (LAS)
shall reside in the host control system in redundant H1
network interface cards.
An additional backup LM Link Master (B/U LAS Link Active
Scheduler) shall be configured for all networks and shall
reside in the network device with the lowest field node
address. The Backup LAS should be placed in a separate
device that does not have controlling functions.
Primary and secondary interfaces should sit in separate
backplanes with separate CPUs, preferably in separate
control panels. Similarly, the primary and secondary power
supplies should not share the same backplane. Having
redundant interface cards, CPUs, and power supplies in the
same backplane is self-defeating since the backplane is a
single point of failure.
Each network shall be configured for automatic fail-over to
the Back-up LAS in the event of Master LAS failure.
Carl Ellis
Measure First
| Is This Answer Correct ? | 4 Yes | 0 No |
what is basic working principle of Governer in power plant?
wht is dcs architecture ? can u give example?
the 3 most common transmitter protocol being in refinery or qatar gas and aramco.
When doing a liquid seal on a differential flow transmitter , most of the time the sealing liquid will be heavier then the process fluid. For wich application will the sealing liquid be lighter than the process fluid if transmitter is mounted below the process line.
Can I put my meter across an RTD to check it safely witout tripping the equipment when it is connected to an monitoring device eg.RTD module or IQ 1000
WHAT IS TSI? HOW ITS WORK
why r using 250 resistances
If the vibration probe near to the shaft,then output voltage will be decreased r increased?How?
is motorized valve closed when power shutoff?
Sir, I want junior executive, Instrumentation question papaer for IOCL, Plz send to arabinda.ghosh83@gmail.com
Describe the concept of Gain Scheduling, as currently found as an option in some controllers.
What is the diffirence between Earth and Neutral and What is the required normal voltage between earth and neutral
Civil Engineering (5086)
Mechanical Engineering (4456)
Electrical Engineering (16639)
Electronics Communications (3918)
Chemical Engineering (1095)
Aeronautical Engineering (239)
Bio Engineering (96)
Metallurgy (361)
Industrial Engineering (259)
Instrumentation (3014)
Automobile Engineering (332)
Mechatronics Engineering (97)
Marine Engineering (124)
Power Plant Engineering (172)
Textile Engineering (575)
Production Engineering (25)
Satellite Systems Engineering (106)
Engineering AllOther (1379)