Answer / visakh ctjv

all loop powered transmitters are capable of
withstanding 10 t0 36v dc ...as per the process requirement
it will vary.. insome industries they are using 12v dc
also.. 24 vdc is used because as per ISA there are some
standards wich will match other process reqirement like
24vdc relays for digital control also wecan use 24dc to
energize tis relays

Answer / sanjay goswami

24 VDC potential is safe for use in Oil& Gas industries,230
VAC has hight voltage potential and therefore posses high
risk energy for Oil&Gas and human working on it.
DC power is also clean and does not contain any noise like
AC,therefore for precise instrumentation 24 VDC is the
suitable power.

Answer / mohammed abbas

INSTRUMENTS ARE DESIGN TO WORK ON LOW VOLTAGE BY THE
MANUFACTURER LIKE,YOKOGAWA,HONEYWELL AND ROSEMOUNT.LOW DC
VOLTAGE 24 VDC WHICH IS COMPITIBLE FOR ALL THE CONTOL
SYSYTEM AND THE FIELD INSTRUMENT WHICH IS DESIGN WILL WORK
ON 24 VDC WHICH IS REQUIRE TO ENERGIES THE ELECTRONIC PART
ALSO.IF WE USE 230VAC MEANS IT IS DANGER BECAUSE WHICH WILL
CAUSE A ACCIDENT OF LIFE ALSO IF ANY UNSKILLED TECHICIAN
WORK ON THAT INSTRUMENT.24 VDC IS SAFE FOR HUMAN BEING AS
WELL AS LOW POWER CONSUME,WHICH IS COMPITBLE FOR ALL THE
CONTROL SYSTEM AND ALL THE INSTRUMENTS IS BUILD WITH
ELCTROIC WHICH IS FUNCTIONING ON LOW 12 TO 32VDC.ALL THE
INSTRUMENT DESIGN IS ON THE BASIS OF LOW VOLTAGE AND LOW
CURRENT ONLY.

Answer / narendra mishra

the max voltage is 24v & max current flow throw cable is
27mA so max power loss that cable can bear is 647mW.which
is allowable for the cable designed .

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