PVC/SKYRAD/M1 - Intake Fan Failure

PSP (down_short_hemisp) ventilator fan failed from start of PVC deployment.  Site ops 
repaired/replaced on 8/28. Instrument data are not recoverable.

The down_short_hemisp data are not recoverable but can be re-constructed using the 
short_direct_normal and down_short_diffuse_hemispheric measurements and the following formula: 

Global = Direct * cos(zenith angle) + Diffuse

• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Standard
  Deviation(down_short_hemisp_std)
• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Minima(down_short_hemisp_min)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Downwelling shortwave hemispheric irradiance, pyranometer, maxima(down_short_hemisp_max)

• Instantaneous Downwelling Hemispheric Shortwave, Pyranometer Thermopile Voltage(inst_global)