I have a 96volt DC line, and I am trying to get it down to 3.3volts to put into an opamp, and then to put into an ADC so that I can read the voltage on the line. The 96volt line will be prone to spikes when it is turning on and off.
I am thinking of using a voltage divider to get it down to between 0 and 5 volts. The line can go up to 110 volts for a long period of time, so I chose R1 to be 11k and R2 to be 415 ohms. Any thoughts of problems with this design?
I also need to figure out how to prevent voltage spikes (up to 220v) for a short period of time. I am thinking about using a capacitor connected to ground coming off of the voltage divider line. I am worried that this may decrease the accuracy of measuring the voltage.
Would this be the correct way to go, or is there a beter solution?