FRIDGE TIMER SAFE ELECTRCITY

Hi guys. In this post I'm going to present a circuit for energy saving. It is in your fridge not for yours. Surely it will indirectly save your energy by saving your money .Right? As we know electricity is becoming very expensive ( in some countries like Pakistan ). This circuit for a fridge that consume high power during peak hours 6pm to 99pm. It would be worse if there is low voltage on domestic lines. So instead keep it running it is better to turn it off during peak hours and save you energy and money too. This circuit is designed in such a way to turn it off automatically during peak hours. Don't work it would turn on after 2.5 hours. Off around 6pm and switches on again after 2.5 hours.

IC used is 4060:

As engineers we should know what is 4060. The trick is of 4060.it is the binary counter of frequency divider with 10 outputs. It has built in oscillator which is based on three inverters. Basically the value of inverter is determined by the e values of capacitors and resistors connected with it in its pin no 9 and 10 respectively. pin11 is the  (OSC) oscillator into which the pulses enter from the external oscillator. After completing one cycle  each output of ice turns high when it is in the negative transition.. In order to get me time delay output q is omitted so that double time delay is available b/w the outputs q10 and q12.



Inside though is there is an oscillator and 14 series connected bistables ( ripples cascade arrangement).  The signal of the oscillator drive the first bistable which drives the second bistable and so on. Each bistable divides its input signal by two. a total of 15 signals are available, each one is the half of its preceding. Ten of these 15 signals are available on the output of q4 --q14.



Time cycle calculation:

Time t= 2n/ f as =seconds.

N is the selected q output number

F ocs= 1/2.5 (R x C1) = in HERTZ

R is the resistance at pin 10 in ohms and C1 is the capacitor at pin 9 in FARDS.

LETS TAKE AN EXAMPLE.:

If R1 is 1M and C1 is 0.22micro  the basic frequency of ours is >>1/2.5( 1x 10^6 x 0.000,000 22)= 1.8 HZ



HOW THIS CIRCUIT WORKS?

Light dependent resistor (LDR) is used to detect darkness around 6pm. During day light  LDR has less resistance and it conducts. This keeps the reset pin 12 of IC high and the IC remains off with out oscillation. V at R1 adjust the resetting of is at the required light level. Let around 6pm. When the light in the room drops off below the preset value level. ic1 start oscillation. After 20 second pin no 5 turns high voltage and triggers the relay driver transistor T normally the power supply to the fridge is provided through the command NC contacts of the relay. So when the replay triggers the contaacts break and the power to the fridge cut off.

FOR MORE INFORMATION ABOUT CIRCUIT CLICK THIS LINK.