Answer / rajeev

4-20ma is bcoz in older transmiter ckt 3ma is use for it self to ckt operation & 20ma is for saftey purpose bcoz 30ma is dangerous for life.

why we are using analytical instrument in plant ?

1 Answers  

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what is use of communication wire in multipare cable(oil and gas field), why this communication wire not used in single pair cable?

0 Answers  

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i have an interview in Qatar Petroleum. So please provide the all details abt fire & gas systems

1 Answers   Qatar Petroleums,

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what is sliding spool valves?

0 Answers  

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CAN YOU USE MOVING COIL METER FOR MEASURING A.C?

2 Answers   DVC,

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What is the difference between radar and ultrasonic level transmitter? Which method is best and more accurate?

8 Answers  

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Which standard of hazardous area classification used in India?

1 Answers   Orchid,

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what is difference between RTD , thermo couple and thermistor in general ?? (except temperature co-efficient )

5 Answers   Bilt,

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Can anybody explain about wellhead control system.

1 Answers  

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draw the characteristics of chebyshev filter

0 Answers  

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WE Know that different supply voltage of solenoid valve like 24,110,220 etc..how we check the solenoid supply is 24v or 220 NOTE: No specification at device.

2 Answers   OMV,

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what is all types of analyzer in water production plant?

1 Answers   Marafiq,

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