# Pune University BE Mechanical Mechatronics Question Papers

B.E. (Production) MECHATRONICS (Elective – III) (2008 Pattern) (Sem. – II)

Time :3 Hours]                                                                           [Max. Marks :100

Instructions to the candidates:

1)            All questions are compulsory.

2)             Neat diagrams must be drawn wherever necessary.

3)             Pigures to right indicate full marks.

4)            Assume suitable data, wherever necessary.

SECTION – I

QI) a) Explain in detail the advantages and disadvantages of PLC’s                           [8]

b) Compare PLC’s with other types of controllers.                                               [8]

OR

Q2) a) What are the PLC ladder construction limitations?                                             [8]

b) Describe with neat sketch Overall PLC system.                                                [8]

Q3) a) Bypass / control stations increases flexibility of PLC. Explain with neat sketch.   [4]

b)            Discuss in brief any four input / output specifications of PLC. [4]

c)            Explain with neat sketch register / BCD inputs? What are advantages of it? [8]

OR

Q4) a) Explain in detail types of racks in discrete I/O system.                                      [8]

b) What is I/O rack and table mapping? Explain the process with neat sketches.        [8]

Q5) a) What is the necessity of Analog system in PLC’s? How to give instructions for analog input modules.                                                                                                               [8]

b) Explain with neat sketch transformation of an analog signal into a binary or BCD value.                                                                                                        [10]

Q6) a) Explain with neat sketch transformation of binary data into an analog signal.        [8]

b) An input module, which is connected to a temperature transducer, has an A/D with al2-bit resolution. When the temperature transducer receives a valid signal from the process (100 to 600°C), it provides, via a transmitter, a + 1 to +5 VDC signal compatible with the analog input module. [10]

i)             F ind the equivalent voltage change for each count change (the voltage change per degree Celsius change) and the equivalent number of counts per degree Celsius, assuming that the input module transforms the data into a linear 0 to 4095 counts, and

ii)           Find the same values for a module with a 10-bit resolution.

SECTION – II

Q7) a) What is the necessity of special type of I/O modules? Explain in detail it’s types. [8]

b) Explain with neat sketch Proportional-integral-derivative module (PID). [8]

OR

Q8) a) What are positioning interfaces? Explain with neat sketch PLC system using stepper modules to control three axes.                                                                         [8]

b) Fuzzy logic modules work with other modules to input and output process information according to fuzzy control algorithms. Explain with neat sketch.   [8]

Q9) a) Explain Counters used in PLC programming. Write each specification counter and use of the same in program.                                                                                         [6]

b)            Given four push to ON switches. PB1 for START, PB2 for STOP, PB3 for RED and PB4 for GREEN button. The objectives are

i)              The START button should start the process.

ii)           STOP button shell stop it immediately.

iii)         When PB3 is pushed and PB4 is not pushed RED light should be ON

iv)         When PB4 is pushed and PB3 is not pushed, GREEN light should be ON

Write Boolean equation of each rung you write.

Write PLC ladder program using Ex-ON and /or EX-OFF condition symbols.

Write all the assumptions you do e.g. PB2 is connected to which input, etc.    [12]

Write a comment on Arithmatic instructions used in PLC programming. [6]

For a bottle filling plant, a conveyor is to be used. It has two locations namely LI and L2, poximity switches of NO type. The START button (Push-to-ON) and STOP button (Push-to-ON). The conveyor starts when START button is pushed and stops when STOP button is pushed. The LI proximity, when ON again starts the conveyor and L2 proximity when ON it stops the conveyor. Write a PLC program for the same.

Write Boolean equation of each rung you write.

Write PLC ladder program using Ex-ON and / or Ex-OFF condition symbols.

Write all the assumptions you do e.g. PB2 is connected to which input, etc.           [12]

What are types of thermal transducers? Explain with neat sketch construction and working of RTD.                                                                                                                               [8]

Explain linear variable differential transformer (LVDT) mechanism with it’s any one application.                                                                                                                               [8]

OR

What are flow transducers? Explain with neat sketch Motion Detection Fluid Flow Meter.        [8]

Explain with neat sketch construction and working of any one strain gauge.          [8]