I need help making my Vac LED indicator circuit more reliable.
I have been using a design based on the description "Special-purpose diodes" http://www.allaboutcircuits.com/vol_3/chpt_3/12.html for my AC power indicator.
I have a design that I am using for both 120 & 240Vac. It consists of a series network of a 0.22uf Cap, a 1.2k ohm resistor and a Blue LED. I have also placed a 1n4002 100v 1 amp rectifier diode in parallel but in opposite polarity to the LED to protect it from a reverse over voltage situation.
I am using this circuit on a power strip to just give me a visual indication that power is on. I am having trouble with the LED burning out when I plug appliances into the power strip. It doesn't happen every time but I can cause it to happen by plugging and unplugging an appliance multiple time rapidly. There must be a peak surge that occurs and kills the LED. I have tried increasing the series resistor all the way up to 2.7k ohms but it still will fail. It also fails allot easier on the 240Vac application.
I would like to know if anyone has any ideas on how I can make this design more reliable?
I have been using a design based on the description "Special-purpose diodes" http://www.allaboutcircuits.com/vol_3/chpt_3/12.html for my AC power indicator.
I have a design that I am using for both 120 & 240Vac. It consists of a series network of a 0.22uf Cap, a 1.2k ohm resistor and a Blue LED. I have also placed a 1n4002 100v 1 amp rectifier diode in parallel but in opposite polarity to the LED to protect it from a reverse over voltage situation.
I am using this circuit on a power strip to just give me a visual indication that power is on. I am having trouble with the LED burning out when I plug appliances into the power strip. It doesn't happen every time but I can cause it to happen by plugging and unplugging an appliance multiple time rapidly. There must be a peak surge that occurs and kills the LED. I have tried increasing the series resistor all the way up to 2.7k ohms but it still will fail. It also fails allot easier on the 240Vac application.
I would like to know if anyone has any ideas on how I can make this design more reliable?