Answer / paresh koradia

Communicator does not provide the 4-20ma or any kind of
supply voltage.However, we can force the output (4-20ma) of
the transmitter by communicator. The transmitter requires
an external power supply and the communicator just
connected parallely is used to either read the diagnostic,
process or else data from the transmitter plus to write
certain data like tag no., tuning parameters, calibration
data, ranges, etc.

Answer / ako

no hart communicator can only read and convert the
pressure,temperature and voltage.only multiprocess
calibrator can provide 4to20ma source

Answer / jigar anadkat

During simulation mode, HART communicator can provide 4-20
mA. However it will not be merely considered as a part of
calibration but the loop testing.

what is mean by live zero and dead zero

3 Answers  

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How signals can be taken through modbus?

1 Answers  

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1. How many output signals do wew have in process control? 2. Could you write down the names of the pre-commissioning and commissioning stage test instruments and explain them (more than 5 items)? 3. What is the first step to commission a transmitter on service? 4. What is RTD? 5. Find the output value in MA of a temperature transmitter (RTD Type) at 120degree celius? 6. What is the O/P signal of a pneumatic transmitter? 7. What is the O/P signal of an elctronic transmitter? 8. What is the close loop and open loon?

4 Answers  

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why we should maintain neutral earth voltage below 1V while calibration? why cant it be 1.2V or 2V

0 Answers   Hospira,

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if drum level is low what is interlock? i mean we put interlock to fd fan or id fan ?

4 Answers  

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few questions on RS 232,1 question on relationship of impedance and turns ratio, many questions on flowmeters

0 Answers   Monnet,

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Explain " FAIL SAFE " feature in temp. measurement.

1 Answers   Bapco Bahrain Petroleum Company,

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Air pressure in a pressure vessel can rise or fall at up to 2.5kpa/s.The pressure is sampled every 0.5 seconds.If range of the the pressure indication is 0 to 1500 kPa, what is the max value of the error due to sampling in % of Span

2 Answers  

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What is difference b/w absolute & gauge pressure? EXPLAIN

2 Answers   IFFCO,

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diff bw range and span?

3 Answers  

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what is vfd(variable frequency drive)?type of vfd.

2 Answers  

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In split range control, we will control 2 outputs with time interval. Eg :(with 4-20 ma signal, for 4-12 ma we are operating one control instrument like valve & for 12-20ma we are operating other control instrumet (other valve). If we get a signal of 15ma to first instrument (Valve 1), what will happened to the first valve, and if we get signal above 20 ma to 2 valve what will happened ?

3 Answers  

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