Hello there,
I am building a 555 oscillator circuit for a college project and come across a small difficulty. It is a input circuit for a PLC which will implement Load Shedding.
The 555 circuit is to simulate the pulse output from a Digital Supply Meter, where each pulse were to equal 1kWh say (this value is not important at this stage). So I have an astable 555 circuit arrangement, with a potentiometer to vary the frequency output. This output is connected to a counter within a PLC. The PLC will give an output, once the counter reaches a set value, that will cause the frequency of the 555 circuit to reduce by a set amount. (eg. 5Hz)
I have tried configurations of increasing the values of the R1, R2, or C1 to create a decrease in the frequency by so much. But this reduction of frequency ends up proportional to the Potentiometer.
I am building a 555 oscillator circuit for a college project and come across a small difficulty. It is a input circuit for a PLC which will implement Load Shedding.
The 555 circuit is to simulate the pulse output from a Digital Supply Meter, where each pulse were to equal 1kWh say (this value is not important at this stage). So I have an astable 555 circuit arrangement, with a potentiometer to vary the frequency output. This output is connected to a counter within a PLC. The PLC will give an output, once the counter reaches a set value, that will cause the frequency of the 555 circuit to reduce by a set amount. (eg. 5Hz)
I have tried configurations of increasing the values of the R1, R2, or C1 to create a decrease in the frequency by so much. But this reduction of frequency ends up proportional to the Potentiometer.