Subject: | NSA/GNDRAD/C2 - Upwelling PIR measurement - spikes in thermopile signal |
DataStreams: | nsagndradC2.00, nsagndrad20sC2.a1, nsagndrad60sC2.b1
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Description: | ULH measurements have many spikes at this site. On 2/03, the anomalous spikes become
frequent and are very noticeable from 0027 - 0445 UTC. Negative and positive spikes occur on
seemingly random days until 5/27/2004. Extensive troublshooting could not resolve
problem, including a datalogger changout on 4/22. Problem seems to have resolved itself with
the last spikes occuring on 5/27/2004 approximately 1500GMT. No problems with upwelling
PIR noise are evident up until and after the conversion from Zeno to Campbell dataloggers
on 11/22/2004. |
Measurements: | nsagndrad20sC2.a1: - Instantaneous Upwelling Pyrgeometer Thermopile Voltage, Pyrgeometer(inst_up_long_hemisp_tp)
- Instantaneous PIR1 uncorrected irradiance(pir1_voltage)
nsagndradC2.00: - Raw data stream - documentation not supported(Raw data stream - documentation not supported)
nsagndrad60sC2.b1: - Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer,
Maxima(up_long_hemisp_max) - Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer,
Standard Deviation(up_long_hemisp_std) - Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer,
Minima(up_long_hemisp_min) - Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer(up_long_hemisp)
- PIR1 unshaded minimum(pir1_min)
- PIR1 unshaded mean(pir1_mean)
- PIR1 unshaded maximum(pir1_max)
- PIR1 unshaded standard deviation(pir1_sd)
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Subject: | NSA/GNDRAD/C2 - Incorrect calibration coefficients applied to upwelling(Gndrad)PIR |
DataStreams: | nsagndradC2.00, nsagndrad60sC2.b1
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Description: | An insitu test comparing the Gndrad PIR and the Gndrad IRT at the NSA was performed from 6
Jan 2005 to 12 Jan 2005. The radiometer mentor requested the Eppley single calibration
coefficient for the PIR replace the 4 coefficients method developed by NREL. The Grndrad
PIR compared closer to the Gndrad IRT during this period. However, the radiometer mentor
believes the 4 coefficient PIR irradiance measurements remains superior to the single
coefficient Eppley PIR measurement method. Further questions should be directed to the
radiometer instrument mentor. |
Measurements: | nsagndradC2.00: - Raw data stream - documentation not supported(Raw data stream - documentation not supported)
nsagndrad60sC2.b1: - Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer,
Maxima(up_long_hemisp_max) - Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer,
Standard Deviation(up_long_hemisp_std) - Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer,
Minima(up_long_hemisp_min) - Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer(up_long_hemisp)
- PIR1 unshaded minimum(pir1_min)
- PIR1 unshaded mean(pir1_mean)
- PIR1 unshaded maximum(pir1_max)
- PIR1 unshaded standard deviation(pir1_sd)
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