Answer / andy

electro-catalytic detectors detects change in resistance
whereas ir-type detectors detects changes in intensity of IR
spectrum and alerts the system whenever they detects a fire

Answer / gautam_etrx.engg

Ultraviolet rays (Earlier it was infrared rays)

Answer / faiyaz

Fire detector detect the fire like UV-ultra violet ray and IR means Infra ray both are fire one is small fire and one is big fire generally used in Hazard area like compressor and condensate area

Answer / saumyajit

in fire detectors normally we use photo resistors,which is used in wheatstone bridge circuit,in photo resistor conductivity changes as light intensity change.or we cud use photo diodes.(PN-diode,PIN-diode,avelanche diode)

what is piezo electric transducer?its principle?

2 Answers  

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Can anybody tell me the exact explanation for Functional calibration?When it should be done on process or on lab? Advanced Thanks

2 Answers  

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Calculate the maximum pressure drop that can be allowed to occur across a control valve, so that we can prevent cavitation / flashing from occurring. Use the following formula: Δ P allow = Km (P1 – PvapourA) where, Δ P allow - the maximum allowable differential pressure for sizing purposes, or terminal pressure drop; Km- the valve recovery coefficient from the manufacturer’s catalogue; P1 - absolute inlet fluid pressure; PvapourA - absolute fluid vapour pressure at the inlet temperature; Use Atmospheric pressure = 101.3 kPa, P1 = 1200 kPa(g), PvapourA = 4 kPa, KM = 0.72

0 Answers  

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WHY RESISTANCE TEMPERATURE DETECTOR IS AN ACTIVE DEVICE

2 Answers  

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I need to know steps to Calibration Valve Guard......

0 Answers  

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we callculat main steam flow by D.P. but where is H.P. & L.P. IN Orfics?

3 Answers  

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Tyes of interface level measurement and how to use that technique for interface level measurement,

0 Answers  

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Gas equation

0 Answers   CCIE,

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CAN WE CALIBRATE LEVEL TRANSMITTER USING HART COMMUNICATOR WHEN WATER LEVEL IS PRESENT IN THE BOILER SHELL?

4 Answers   Chemin, Emerson,

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Why do we use 24V DC supply in instrumentation? What are its merits and demerits??

1 Answers   JSW, MJPRU,

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What is the difference between HMI,SCADA and MMI,not abbrevation?

7 Answers   HCL,

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pls give me presant awerness quistion and answer in my emailid.

0 Answers  

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