Question { 15461 }

which type signal in & out in dcs

Answer

1) AI - ANALOG INPUT THIS FEED BACK SIGNAL FORM (4 - 20 mA)
2) AO - ANALOG OUTPUT COMMAND GIVEN FROM DCS (4 - 20 mA)
3) DI - DIGITAL INPUT (FEED BACK 0 OR 1, HIGH OR LOW)
4) DO - DIGITAL OUTPUT (PICK UP THE RELAY 0 OR 1, HIGH OR
LOW COMMAND GIVEN FROM DCS)
5) T/C INPUT- FOTR THERMOCOUPLE
6) RTD INPUT- FOR RTD
7) THIRD PARTY COMMUNICATION- LIKE PLC INPUT OUTPUT,
CONTROLLER INPUT OUTPUT (IT IS DIFFERENET FOR DIFFERENT DCS)

Question { 4574 }

i have 80cm water tank.how can i use DPT as level
mesurment.pls give specs for that..?

We have air comp.from that moisture comeout to one tank.i
want to mesure level of water in that tank and then after
operat one sov to dicharge water after high level.

Answer

TAKE TWO TAPINGS, ONE AT 5CM (HP SIDE)ONE AT 75 CM (LP
SIDE). NOW CONNECT THE DPT AS PER HP AND LP CONNECTION AND
IN Tx. ALSO DEFINED THE LSV AND USV IN Tx. IT WILL GIVE U 4
MA AT 5 CM AND 20MA AT 75 CM OF THE TANK LEVEL.

NOW THE SAME THING U CAN DO FOR THE COMP. MOISTURE LEVEL.
TO OPERATE SOV U HAVE TO USE THE ANALOG SIGNAL COMING FROM
DPT AND WITH USE OF THIS U HAVE TO GENERATE A DO COMMAND
(24V). THIS COMMAND WILL DIRECTLY GO TO SOV(24 V) WHEN
LEVEL IS HIGH.

SUPPOSE DPT TAG IS (PI01)
SET PI01.HH AT 75 CM.. AND USE THIS SIGNAL TO GENERATE THE
DO FOR SOV USING A SWITCH LOGIC IN DCS

Question { Essar, 22179 }

what is the working principle of vortex flowmeter

Answer

vortex shedding phenomenon

Question { Honeywell, 34363 }

what is the meaning of reverse action and forward action of
control valve...

Answer

REVERSE ACTION CV = AIR TO CLOSE = AIR FAIL TO OPEN

DIRECT ACTION CV= AIR TO OPEN =AIR AIL TO CLOSE

Question { Honeywell, 15345 }

what is meaning of software redundency and hardware
redundency?

Answer

redundancy is the duplication of critical components of a
system with the intention of increasing reliability of the
system, usually in the case of a backup or fail-safe.

IF IT IS FOR SOFTWARE THEN IT IS SOFTWARE REDUNDANCY(LIKE
BACKUP OF DCS)

IF IT IS FOR HARDWARE THEN IT IS HARDWARE REDUNDANCY(LIKE
COMPUTER MONITER)

Question { 8890 }

HELLO FRIENDS plz tell me which are the PROTOCOLS we are
using in PLC

Answer

Protocol Transport

Ethernet/IP TCP/IP
AB/CSPv4 TCP/IP
Modbus/RTU UDP/IP
DF1 Radio Modem UDP/IP