SGP/SIRS/E15 - NIP cable failure results in missing data

The NIP began reporting -9999 (missing) for all direct normal 
              downwelling shortwave radiation.  Maintenance 6/8 revealed a 
              broken cable. Cable was repaired and NIP data returned to normal.

Disregard this data

• (Raw data stream - documentation not supported)

• Instantaneous direct normal shortwave irradiance, pyrheliometer thermopile
  voltage(inst_direct_normal)

• Shortwave direct normal irradiance, pyrheliometer(short_direct_normal)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• Shortwave direct normal irradiance, pyrheliometer, minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)