Data Quality Reports for Session: 147736 User: moore Completed: 02/07/2013

TABLE OF CONTENTS

DQR IDSubjectData Streams Affected
D051202.1NSA/SKYRAD/C1 - Reprocess: Incorrect datalogger program affecting PIR1 and PIR2
downwelling longwave		nsaskyrad20sC1.a0, nsaskyrad60sC1.b1


DQRID : D051202.1
Start DateStart TimeEnd DateEnd Time
11/04/2004190009/09/20052142
Subject:
NSA/SKYRAD/C1 - Reprocess: Incorrect datalogger program affecting PIR1 and PIR2 
downwelling longwave
DataStreams:nsaskyrad20sC1.a0, nsaskyrad60sC1.b1
Description:
The excitation delays using in measuring the PIR1 case thermistor commonly named "Case1" 
and the PIR2 dome thermistor called "Dome2" were discovered to have been incorrectly set 
to 0 in the Skyrad datalogger program when the new CR23X based Skyrad loggers were 
installed.  The result of no delay in these measurements results in an error in the measured 
resistance of the thermistors, Case1 and Dome2 and thus the calculated PIR1 and PIR2 
irradiances.  The errors are inversely proportial to temperature.

Users can apply the temperature dependent irradiance corrections shown in the table below. 
 Recall that the reported uncertainty of PIRs is typically +-.25% to +-.5% or 1 to 2 
W/m2.  The error corrections become the same order of magnitude or larger than the 
instrument uncertainties at or below 260K or 9F. 

Correction Table for Skyrad (TWP and NSA) DIR1 and DIR2 Irradiance				
	DIR1	DIR1	DIR2	DIR2
T[F]	Tcase[K]	Correction[W/m2]	Tdome[K]	Correction[W/m2]
109.4	316.13	0.00	316.13	0.00
100.5	311.20	-0.15	311.20	0.12
93.2	307.14	-0.12	307.14	0.10
87.0	303.70	-0.10	303.70	0.08
81.6	300.70	-0.17	300.70	0.14
77.0	298.15	-0.22	298.15	0.18
59.4	288.35	-0.34	288.35	0.27
47.4	281.72	-0.23	281.72	0.18
38.5	276.74	-0.42	276.74	0.34
31.3	272.77	-0.48	272.77	0.38
25.4	269.48	-0.61	269.48	0.49
20.3	266.67	-0.67	266.67	0.54
16.0	264.25	-0.82	264.25	0.66
12.1	262.11	-0.98	262.11	0.79
8.7	260.19	-0.97	260.19	0.78
5.6	258.46	-1.07	258.46	0.86
2.7	256.89	-1.17	256.89	0.94
0.1	255.44	-1.33	255.44	1.07
-2.3	254.11	-1.41	254.11	1.13
-4.5	252.87	-1.43	252.87	1.15
-6.6	251.71	-1.52	251.71	1.22
-8.5	250.63	-1.63	250.63	1.31
-10.4	249.62	-1.73	249.62	1.39
-12.2	248.58	-1.79	248.58	1.44
-15.4	246.82	-1.93	246.82	1.55
-18.3	245.23	-2.05	245.23	1.65
-20.9	243.78	-2.22	243.78	1.78
-23.3	242.44	-2.36	242.44	1.89
-25.5	241.21	-2.58	241.21	2.07
-27.5	240.07	-2.65	240.07	2.13
-29.5	239.01	-2.75	239.01	2.21
-31.3	238.00	-3.02	238.00	2.42
Measurements:nsaskyrad60sC1.b1:
  • down_long_hemisp_shaded2_std
  • down_long_hemisp_shaded2_min
  • down_long_hemisp_shaded2_max
  • down_long_hemisp_shaded1_max
  • Irradiance, longwave, downwelling, hemispheric, shaded pyrgeometer1(down_long_hemisp_shaded1)
  • down_long_hemisp_shaded1_std
  • Irradiance, longwave, downwelling, hemispheric, shaded pyrgeometer2(down_long_hemisp_shaded2)
  • down_long_hemisp_shaded1_min
nsaskyrad20sC1.a0:
  • Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer1)(inst_down_long_hemisp_shaded1_tp)
  • Irradiance, longwave, downwelling, hemispheric, thermopile (Shaded Pyrgeometer2)(inst_down_long_hemisp_shaded2_tp)
  • inst_down_long_shaded1_case_resist
  • inst_down_long_shaded2_dome_resist
  • inst_down_long_shaded2_case_resist
  • inst_down_long_shaded1_dome_resist

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