Programming Examples IV

Example A:
Use the instructions (set, reset) with the timer (SM0.4) to turn an output on/off after several pulses from the SM0.4 timer.

and timing diagram:


Example B:
The next figure represents the process of making tea every day in the morning for seven days (water in the tank is enough for 7 days only)

Procedure:
When pressing the ‘start’ button, the valve 1 (V1) opens,so the water pass through the valve to the heating tank. And when the water level reaches the float switch (FS), the valve should close and heating must begin.

When the temperature reach the required level the thermostat disconnects the heater and opens valve 2 (V2) for 10 seconds then the alarm bell is activated (as a sign that the tea jug is filled now with hot water)