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 the cv of a control valve?

2 Answers   CCIE,

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1. what is modbus cable? 2. what kind of communication we are using for the interface of DCS, ESD and Third party cabinets? 3. What is serial communication and peer to peer communication?

0 Answers  

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sir ,iam in dem urgent need of HPCL Paper of Instrumentation Branch plz send me at your earliest convenience at ujjwal_sharma1983@yahoo.com

0 Answers   ONGC,

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What does PCU means with respect to Dead Weight Tester?

1 Answers   SGS,

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How can we calibrate pressure and flow transmitter in the field(online)?

3 Answers   Aramco, Reddy Labs,

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in transmiters(rose mount) how to check output 4-20ma ? and input 24v? i need exact explanation?

2 Answers   Adhunik,

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For 150 mtr cable run from DCS panel to transmitter (24 VDC with 4-20 ma output), need cable size. 1.5 sqmm is suitable?

2 Answers   NA,

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Will Intergraph support SmartPlant Instrumentation in an AutoCAD or MicroStation environment on a long-term basis?

1 Answers   Siemens,

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What is the meaning of wet leg

0 Answers  

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Close loop and open loop.

3 Answers   CCIE,

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If hart communicator provide 4-20ma source to any transmitter during the callibration?

3 Answers   Hyundai,

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how can we measure the pressure in underground cooling water pipeline by using pressure transmitter?what about the tapping position?

2 Answers  

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