Aakif

you had already got the right Q2c & Q3c Answer.But remember that in Q2c logic you have start toggle button is used becoz there is also stop button thats why you have to latch the start button in logic and can delatch by stop button to stop process.One more thing in logic is that when next cycle will start the y1 will operated first due to drop of level sensor 1 first so you also have to modify that it wont start until sensor 2 is also 0. i think you had understand my words, if not then feel free to ask any question..ok dear . I am Also a PLC engineering and doing projects in pakistan and dubai......bye