Why plc require in analog input 4-20amp & 0-10 volt?

0 Answers  

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what is mass flow meter principal?

4 Answers   GIL,

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Explain about SOURCING & SINKING concepts in PLC to field sensor wiring ?

4 Answers   GATE,

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Why we used cage in control valve?

8 Answers  

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EXPLAIN PROPOTIONAL INTEGRAL DERIVATIVE CONTROL ACTION?

1 Answers  

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Can we use twisted pair cable instead of ethernet for communication?

1 Answers   Yokogawa,

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Emergency Shutdown Systems/ Plant Shutdown System.

0 Answers   CCIE,

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Why Flow measurement has to use Square Root

5 Answers   Hindalco, Petronas,

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what is modbus?and why use it?what benifit

2 Answers  

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7. What are tri-state devices and why they are essential in a bus oriented system

1 Answers  

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A PLC is programmed to drive three motors A, B and C as follows : After running motor A for an hour, motor B should get ON and motor A should get OFF. And after running motor B for an hour, motor C should get ON and motor B should get OFF. And after running motor C for an hour, motor A should get ON and motor C should get OFF. (That is, a cyclic repetition with time period one hour) Now, the second condition is: If any motor gone faulty and is tripped, the consecutive motor should get ON and the faulty (tripped) motor should be eliminated from cyclic repetition. The remaining two motors should bear the cyclic repetition of one hour each. (For healthy motor take logic as high and for tripped motor take logic as low) Now, the third condition is: When motor A load(Amps) exceeds 60% of its rated load, motor B should get ON in parallel to motor A. And when both motors A & B are running in parallel, and if their load exceeds 60% of their rated load, motor C should also start in parallel to A & B. [Here the cyclic repetition is eliminated, until their loads become normal(40%)] [Take logic high(1) for load at 60% and logic low(0) for load at 40%] Now draw a flow chart or a ladder diagram to fulfill the above condition.

0 Answers   MNC,

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WHAT IS A CALLIBRATION? WHAT IS MEEAN BY LOOP CHECKING INCLUDES PRESURE, THERMOCOUPLE,TT,DT?

5 Answers  

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