The Total Irradiance Monitor ( Tim ) : Instrument Design

  title={The Total Irradiance Monitor ( Tim ) : Instrument Design},
  author={Greg Kopp and George E. Lawrence},
The Total Irradiance Monitor (TIM) instrument is designed to measure total solar irradiance with an absolute accuracy of 100 parts per million. Four electrical substitution radiometers behind precision apertures measure input radiant power while providing redundancy. Duty cycling the use of the radiometers tracks degradation of the nickel-phosphorous absorptive black radiometer interiors caused by solar exposure. Phase sensitive detection at the shutter frequency reduces noise and simplifies… CONTINUE READING