Can youi help me solve these PLC questions for the traffic light program below 1

Question

Can youi help me solve these PLC questions for the traffic light program below

1.Explain the function of each timer.

2.Explain the logic of each rung.

3.How would you adjust the amount of time the North/South lights remain red?

4.How would you adjust the amount of time the East/West lights remain yellow?

Ladder logic program TON T4:2 TIMER ON DELAY EN Timer T4:0 Time base DN 1.0 DN Preset Accumulated T4:0 TON TIMER ON DELAY Timer T4:1 DN Time base 1.0 DN Preset 25 Accumulated T4:1 TON TIMER ON DELAY T4:2 Timer DN Time base 1.0 DN Preset Accumulated T4:0 TON TIMER ON DELAY T4:3 Timer EN Time base 1.0 DN Preset Accumulated Red T4:0 T4:0 DN North/south T4:1 T4:1 Green EN DN North/south Amber T4:2 T4:2 EN DN North/south Green T4:3 T4:3 DN EN East/west T4:0 T4:3 DN DN East/West T4:0 DN East West outputs L1 North/south traffic lights Red Red North/south Amber Amber North/south Green Green North/south East/West traffic lights Red Red East/west Amber Amber East/West Green Green East/west

Explanation / Answer

(a) TON - TIMER ON DELAY

Bit 0 -12 : Internal use

Bit 13 : DN - This bit is on when the accumulator value reaches the preset value

Bit 14 : TT - Timer Timing - this bit is on when timer is timing

Bit 15 : EN - This bit is on when the timer is energised

In the given ladder diagram,

First timer - Once T4:0 goes down, the timer will start timing. The base time is set to 1.0 and preset is 30. Therefore, the total time is upto 30.

Second timer - Once T4:3 is energised, the timer will start timing. The base time is set to 1.0 and preset is 25. Therefore, the total time is upto 25.

Third timer - Once T4:1 goes down, the timer will start timing. The base time is set to 1.0 and preset is 5. Therefore, the total time is upto 5.

Fourth timer - Once T4:0 goes down, the timer will start timing. The base time is set to 1.0 and preset is 30. Therefore, the total time is upto 30.

(b) The four timer provide the delay time for the traffic light to be ON.

When timer T4:0 is energised, the Red light at the North/South signal glows

When timer T4:1 is energised and not Down, the Green light at the North/south signal glows

When timer T4:2 is energised and not Down, the amber light at the North/South signal glows

When timer T4:3 is energised and not Down and till 4:3 is not Down, the greem light at east/West glows

When T4:3 is down and till T4:0 is not down, the Amber light in East/West signal glows

When T4:0 is down, the red light at East/West signal glows

(c) The timer for North/south Red light

The time for the North/south Red light is adjusted by adjusting the timer T4:0.

The time delay is given by Timer Base time multiplied by the Timer preset value. By adjusting these two parameters, the amount of time for the north/souh red light can be adjusted.

(d) East/West light to remain yellow

The time for the east/west yellow light is adjusted by adjusting the timer T4:0 and T4:3.

The time delay is given by Timer Base time multiplied by the Timer preset value. By adjusting these two parameters, the amount of time for the east/west yellow light can be adjusted.

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