Answer Posted / sks

AC drives known as VFD(variable frequency drives) operate
differently from DC drives known as VSD(variable speed drives )
the most basic difference being that DC drives may have a
constant dutycycle( ON to On-Off ratio) on PWM signal but AC
drives must have a variable duty cycle throughout as they
are frequency based and can't be instantly increased or
stopped at min or max frequency.

1.what is the effect of vapour presuure in orifice plate flow measurement 2.which is more effective 2 pressure sensors or one single differential pressure sensor in orifice plate measurement 3.how to design a v/i converter and i/v converter 4.how many type of thermocouple are there 5.how many leads are there in thermocouple measurement 6.how pressure sensors are connected in level measurement in differential pressure method 7.what is the output of capacitive pressure sensor (ac or dc),how its o/p is signal charactarized 8.what is the physical meaning of discharge coeeficient,why it is calculated,orifice plate what is its value,why it is less than 1,Q at upstream is equal to or not equal to Q at downstream of orifice plate why?what is vena contracta in orifice plate 9.why rotameter is called variable area flowmeter,it can measure flow even if area is not varying,why it is made tapered 10.design a 10 bit counter ,which counter you will prefer 11.how to remove self heating error in RTD 12.which is more sensitive pt100 or pt50 13.why thermocouple are connected in parallel 14.what is lead contact error in RTD,how to avoid 15.what is P,PI,PID,PD controller,why there is no ID controller 16.what is override,split range,sequential,ratio,feedforward,cascade controller 17.why we moved from SR to JK and then JK to master slave JK flipflop,give correct reason 18.how to measure level of a closed container which contains vapour and liquid,remember no vapour gas should be leaked,so ultrasonic and capacitive is not an option,design another method 19.how to design horse race counter including sensors and signal conditioning element 20.what is bevelling

2467

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Why 4-20 amps is being used in instruments? Why cant we use any other range instead of 4-20 amps? Why only 4 amps is taken as lower limit and why 20 amps is taken as the higher limit?

1565

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we are using centum vp as monitoring with Dell precision work station T3600 but some times PC(s) are restarted automatically . how we can solve this problem? thanks

2230

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State four different types of flow measurement, for gas flow measurement MMSCFD is the common unit expand the unit and specify significance of word S in the unit.

2096

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1- Explain about HPM 2- What is the FSC and explain the configuration of FSC 3- explain the complete loop of vibration, how it works (field to control room) 4- What is the use of proxymitter? 5- During job your partner effected with H2S then what you have to do. 6- what type of gland packing uses when valve glind is leaking.

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There are two chlorination tonners both are connected to two pressure swithes and the pressure switch is connected to SOV which operates the valve to changeover the tonner selection i.e if pressure one tonner goes low the other tonner should come in line if it is inautomatic selection design a circuit using relays ?

2009

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How we connect a instrument with ground, Give brief explanation with help of diagram?

2143

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How to calibrate smoke Dectector

1667

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steps for installing orifice plate?

1895

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what are procedure of sox-nox calibration

3034

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how can we tune a PID. If it is by zeiger nichols method..please explain briefly with help of an example.

2518

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where are following valves are applicable to install. can any valve be installed any line. globe valve butterfly valve boll valve gate valve

1827

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Which topics are covered in Process Control?

2212

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what is cold loop? difference between hot and cold loop?

2303

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Why thermo wells are used? What materials are used in thermo wells?

1171

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