Atmega328 PWM controller with R/E and Relays

A combined final prototype of two recent projects used to control a 12v air blower in a special project, This involves 220V UV lamps, used to generate O3, and a 12v high speed air blower to blow air through the UV enclosure. Additional cooling fans for the 220v ballasts are also controlled from this PCB. The device is used to generate O3 for water purification as well as other O3 applications. The PCB is double layer with SMD components on the top side only, I have made used of the standard Arduino Nano circuit, with some modifications, most significant being the level conversion of the PWM output to the blower to 12v. This was done with a BSS138 N-MOS, The two 12v cooling fan's are also controlled with BSS138's but this time in switch configuration. PCBWay did their usual excellent job with the manufacturing. Thank you