Hi MarkT,
Thanks for the answer,
To keep everything out of equation I disconnected all my PIRs and kept the arduino to the minimum.
I measured the voltage across the +5 and GND.. while the Flourascent light is flickering.
I saw voltage spikes upto 6 or 7 sometimes even more during this and hence the AtMega is restarting.. Is that possible?
Will atmega reboot when this happens?
I use the same wallwart to power the ULN2003 for 8 relays as well as the ATmega . will this cause Ground loop?