Answer / ajith294

Fire and gas system usually as part of a saftey system. the
percentage of Lower Explotion limit shall be dectected by
GAS detector and gives the alarm ,normally 20% is High and
40% is High High alarm.

catalytic bead sensor, semiconductor sensor, infrared point
sensor and ultrasonic sensor are using to detect the gases.

there was no establised standared to difine zero air for
calibration. some procedure says pure nitrogen and some
uses sytetic air. But much more realisitc and practical
using ambient air for zero calibration , when area is
considered to be clean.

for span calibration using 2.5 %Methene (CH4) and balance
nitrogen mixer. 2.5 %Methene (CH4)is equal to the 50 % of
LEL.

Answer / mohamed yousuf

fire and gas system is nothing but to detect the toxic,
flamable and combustible gases in the plant and also for
giving the awarness of the hazardous through beacons and
loudspeakers.

what is difference between OP AMP and differential amplifier?

5 Answers   TCS,

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Why 4mA-20mA current loop selected as standard ???

1 Answers   IMCO, Reliance,

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how to convert cubic metre per hour to newton cubic metre per hour

0 Answers  

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How to isolate a DPT from line in the condition that process must not be disturbed,and process is also critical and no bypass is available.?

4 Answers   Descon,

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A DP transmitter is used to measure the level of an open tank. The drain line of the tank is connected to a control valve, and is configured as, if the level of the tank is 90% the valve should get open 10%. And if the tank level is 10%, the valve should get open 90%. Draw wiring diagram and explain how to configure DP transmitter and control valve using HART communicator. If the span error at output is 1%, what will be the %opening of the control valve at 60% level of the tank?

0 Answers  

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Can anyone say that formula of Converting the Diff. Pressure into Flow in Kg/Cm2 or any explaniation of Orifice Plate, Beta Ratio , How to calculate

1 Answers  

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On drum level, why we are using air to close Control valve?

4 Answers   L&T,

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how many types of spped sensors n vibration sensors?their basic principle n connection?

0 Answers   IOCL, ITC Infotech,

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what is intrument termination what is commisioning

3 Answers  

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Why we use 250 ohm resister in series hart communicator?

3 Answers   Thermax,

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why orfice is not used for main steam flow calculation

0 Answers   OEG,

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What are SMART insuments?

5 Answers  

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