Equipment and Calibration History

History for Licor LI-7500A 75H-2668

Rec No.DateLoc FromTitleLoc ToNotes
4594 2020-07-09 Loaned Disposed Disposed Given to Sabina of Hydrofocus. The DWR grant ended at the end of June 2020, and Bryan requested we hand off a tower to Hydrofocus.
4564 2020-07-09 Sherman Barn Gas Analyzer CO2/H2O Removed Loaned none Removed from Sherman Barn with its decommissioning and given to Sabina of Hydrofocus. The DWR grant ended at the end of June 2020, and Bryan requested we hand off a tower to Hydrofocus.
4497 2020-05-21 Lab none Installed Sherman Barn Gas Analyzer CO2/H2O Installed at Sherman Barn to replace sn 75H-2669 for calibration.
4482 2020-05-20 Lab Calibration Lab none Last calibration: 2020-02-11
AGC=100.3 SDM=0 DAC1=- DAC2=-
Ambient P=100.9kPa, Tair=20.4C, Tdew=9.7C
Zero Air at 800psi, AMP CA04396 408.97 at 600 Tdewspan=16.0
CO2 zero 0.9393 -> 0.9390 Offset: -1.3ppm
CO2 span 1.0171 -> 1.0198 Offset: -1.37ppm
H2O zero 0.9072 -> 0.9082 Offset: 5.7ppm
H2O span 1.0147 -> 1.0119 Offset: 0.05ppm
Notes:
4468 2020-05-19 Bouldin Corn Removed Lab none Removed from Bouldin Corn and brought back to the lab for calibration. It was replaced by sn 75H-2176.
4380 2020-02-20 Lab none Installed Bouldin Corn Gas Analyzer CO2/H2O Installed at Bouldin Corn to replace sn 0042 for calibration.
4369 2020-02-11 Lab Calibration Lab Last calibration: 2019-10-30
AGC=100.4 SDM=0 DAC1=- DAC2=-
Ambient P=100.8kPa, Tair=26.9C, Tdew=-1.59C
Zero Air at 800psi, AMP CA04396 408.97 at 550 Tdewspan=16.0
CO2 zero 0.9393 -> 0.9393 Offset: -0.1ppm
CO2 span 1.016 -> 1.0171 Offset: -0.94ppm
H2O zero 0.9096 -> 0.9072 Offset: 2.7ppm
H2O span 1.0143 -> 1.0147 Offset: -0.01ppm
Notes: Ambient air very dry
4364 2020-02-06 Sherman Barn Gas Analyzer CO2/H2O Removed Lab none Removed from Sherman Barn and brought back to the lab for calibration. Replaced by sn 75H-2669.
4133 2019-10-31 Lab none Installed Sherman Barn Gas Analyzer CO2/H2O Installed at Sherman Barn to replace sn 75H-2667 for calibration.
4128 2019-10-30 Lab none Calibration Lab none Last calibration: 2019-04-26
AGC=100.3 SDM=0 DAC1=- DAC2=-
Ambient P=101.0kPa, Tair=26.9C, Tdew=-10.7C
Zero Air at 900psi, AMP CA04396 408.97 at 800 Tdewspan=20.0
CO2 zero 0.9391 -> 0.9393 Offset: 1.05ppm
CO2 span 1.0169 -> 1.0160 Offset: 0.53ppm
H2O zero 0.9069 -> 0.9096 Offset: -0.9ppm
H2O span 1.0139 -> 1.0143 Offset: 0ppm
Notes: Ambient air was very dry. Joe
4066 2019-08-22 Vaira Gas Analyzer CO2/H2O Removed Lab none Removed from Vaira for calibration. Replaced by sn 0418.
3971 2019-04-30 Lab none Installed Vaira Gas Analyzer CO2/H2O Installed on the Vaira tower to replace sn 74H-2176 for calibration.
3937 2019-04-26 Lab none Calibration Lab none Last calibration: 2019-02-11
AGC=100.0 SDM= DAC1= DAC2=
Ambient P=100.4kPa, Tair=24.5C, Tdew=11.1C
Zero Air at 1050psi, AMP CA4396 408.97 at 700 Tdewspan=16.00
CO2 zero 0.939 -> .9391 Offset: .22ppm
CO2 span 0.018 -> 1.0169 Offset: .59ppm
H2O zero 0.9073 -> .9069 Offset: -2.2ppm
H2O span 1.0117 -> 1.0139 Offset: -.05ppm
Notes:
3947 2019-04-25 West Pond Gas Analyzer CO2/H2O Removed Lab none Removed from West Pond for calibration. Replaced by sn 0418
3880 2019-02-12 Lab none Installed West Pond Gas Analyzer CO2/H2O Installed at WP to replace 75H-2182, which was brought back to the lab for calibration.
3878 2019-02-11 Lab none Calibration Lab none Last calibration: 2018-10-08
AGC=99 SDM=0 DAC1=0 DAC2=0
Ambient P=101.1kPa, Tair=22.5C, Tdew=3.7C
Zero Air at 1150psi, AMP Air 408.97 at 800 Tdewspan=16.00
CO2 zero 0.9394 -> .939 Offset: -1.51ppm
CO2 span 1.0164 -> .018 Offset: -.81ppm
H2O zero 0.9057 -> .9073 Offset: 8.8ppm
H2O span 1.0157 -> 1.0117 Offset: 0.08ppm
Notes: Dewpoint generator dewpoint kept falling b/c it was low on water. I added more DI water and it seemed fine.
3871 2019-01-31 Bouldin Corn Gas Analyzer CO2/H2O Removed Lab none Removed from BC and brought back to the lab for calibration. It was replaced by sn 1594.
3744 2018-10-18 Lab none Installed Bouldin Corn Gas Analyzer CO2/H2O Installed on Bouldin Corn to replace sn 75H-2182 for calibration
3730 2018-10-08 Lab none Calibration Lab none Last calibration: 2018-10-02
AGC=101 SDM=0 DAC1=0 DAC2=0
Ambient P=99.9kPa, Tair=29.3C, Tdew=5.8C
Zero Air at 1500psi, AMP Air 408.97 at 1200 Tdewspan=16.00
CO2 zero 0.9389 -> .9394 Offset: 2.06ppm
CO2 span 1.0172 -> 1.0164 Offset: .38ppm
H2O zero 0.9072 -> .9057 Offset: -8.2ppm
H2O span 1.0238 -> 1.0157 Offset: .17ppm
Notes: Second calibration since chemical swap. Sensor had been running for 5 days, since 10/3 when it had a huge H2O zero offset when analyzing zero gas. I'm not sure why it was reading weird values on 10/3, but the numbers seem ok today, consistent with a chemical swap. In the future, we should let the sensor run for 1 week after swapping internal chemicals, rather than calibrating after only 24 hours.
3721 2018-10-03 Lab none Tested Lab none Tested with zero air and the most recent configuration file from 2018-10-02, but CO2 was reading 7.2 umol/mol and H2O was reading -50 mmol/m3. I'm going to let it run a few more days before checking again.
3720 2018-10-02 Lab none Calibration Lab none Last calibration: 2018-09-26
AGC=101 SDM=0 DAC1=0 DAC2=0
Ambient P=99.9kPa, Tair=26.8C, Tdew=15.9C
Zero Air at 1600psi, AMP Air 408.97 at 1200 Tdewspan=20.00
CO2 zero 0.9392 -> .9389 Offset: -1.47ppm
CO2 span 1.0153 -> 1.0172 Offset: -1.09ppm
H2O zero 0.9056 -> .9072 Offset: 9.2ppm
H2O span 1.0166 -> 1.0238 Offset: -.16ppm
Notes: First calibration after swapping out internal chemicals. Kept the sensor on for 3 days after the swap before the calibration.
3715 2018-09-28 Lab none Maintenance Lab none Swapped out internal chemicals (Ascarite II and Mg(ClO4)2) because the last three calibrations have H2O zero offsets of +/-10 deg C, which is larger than expected. I flushed the analyzer housing with zero air for a few minutes before replacing the chemical bottles.
3704 2018-09-26 Lab none Calibration Lab none Last calibration: 2018-04-04
AGC=100.0 SDM=0 DAC1=0 DAC2=0
Ambient P=100.4kPa, Tair=26.5C, Tdew=13.8C
Zero Air at 1600psi, AMP Air 408.97 at 1200 Tdewspan=16.00
CO2 zero 0.9393 -> 0.9392 Offset: -.27ppm
CO2 span 1.0147 -> 1.0153 Offset: -.27ppm
H2O zero 0.9038 -> .9056 Offset: 10.6ppm
H2O span 1.0146 -> 1.0166 Offset: .05ppm
Notes: "Check PLL" error for the first 30 seconds, then status changed to "OK."
3588 2018-07-12 Bouldin Corn Gas Analyzer CO2/H2O Removed Lab none Removed from BC and brought back to the lab for calibration. It was replaced by sn 75H-2182.
3383 2018-04-05 Lab none Installed Bouldin Corn Gas Analyzer CO2/H2O Installed at BC to replace sn 0035, which was brought back to the lab for calibration.
3378 2018-04-04 Lab none Calibration Lab none Last calibration: 2017-11-28
AGC=100.3 SDM=0 DAC1=0 DAC2=0
Ambient P=100.9kPa, Tair=21.7C, Tdew=8.5C
Zero Air at 100psi, LBL Air 408.97 at 1700 Tdewspan=16.00
CO2 zero 0.9392 -> .9393 Offset: .46ppm
CO2 span 1.0147 -> 1.0147 Offset: -.1ppm
H2O zero 0.9066 -> .9038 Offset: -15.5ppm
H2O span 1.0125 -> 1.0146 Offset: -.04ppm
Notes: Calibrated on LI-7550 sn 674 with 8.5.0 embedded software version. Large H2O offset but last calibration, the offset was +11 mmol/m3 (similar magnitude and opposite sign), so I think it's ok, maybe something wonky last calibration.
3371 2018-03-06 Tonzi-Tower Gas Analyzer CO2/H2O Removed Lab none Removed from Tonzi Tower and brought back to the lab for calibration. It was replaced by sn 0041.
3213 2017-11-29 Lab Gas Analyzer CO2/H2O Floor Installed Tonzi-Tower Gas Analyzer CO2/H2O Floor Installed on the Tonzi Tower to replace sn 75H-2182 for calibration.
3204 2017-11-28 Lab none Calibration Lab none Last calibration: 2017-07-25
AGC=99.9 SDM=0 DAC1=0 DAC2=0
Ambient P=100.6kPa, Tair=21.7C, Tdew=8.9C
Zero Air at 300psi, LBL Air 408.97 at 1700 Tdewspan=16.00
CO2 zero 0.9395 -> .9392 Offset: -1.56ppm
CO2 span 1.0159 -> 1.0147 Offset: 0.64ppm
H2O zero 0.9047 -> 0.9066 Offset: 11.0ppm
H2O span 1.0107 -> 1.0125 Offset: -0.04ppm
Notes: Calibrated on 7550 software version 8.7.5
3155 2017-10-19 Bouldin Corn Gas Analyzer CO2/H2O Removed Lab none Removed from Bouldin Corn for calibration. Replaced by sn 1594
2939 2017-07-26 Lab none Installed Bouldin Corn Gas Analyzer CO2/H2O Replaced 75H-2182.
2936 2017-07-25 Lab none Calibration Lab none Last calibration: 2017-03-14
AGC=100.2 SDM= DAC1= DAC2=
Ambient P=100.4kPa, Tair=21.4C, Tdew=13.0C
Zero Air at 1200psi, LBL Air 408.97 at 2100 Tdewspan=16.00
CO2 zero 0.9392 -> .9395 Offset: 1.41ppm
CO2 span 1.0131 -> 1.0159 Offset: -1.5ppm
H2O zero 0.9041 -> .9047 Offset: 3.2ppm
H2O span 1.0063 -> 1.0107 Offset: -.10ppm
Notes:
2917 2017-07-03 West Pond Gas Analyzer CO2/H2O Removed Lab none Removed from West Pond for calibration. Replaced by 75H-0418.
2846 2017-06-23 West Pond Gas Analyzer CO2/H2O Adjusted West Pond Gas Analyzer CO2/H2O Slated to be removed for calibration but replacement 75H-0418 measured unreasonable H20 levels.
2653 2017-03-15 Lab none Installed West Pond Gas Analyzer CO2/H2O Installed at West Pond to replace 75H-2667.
2649 2017-03-14 Lab none Calibration Lab none Last calibration: 2017-01-30
AGC=99.6 SDM= DAC1= DAC2=
Ambient P=100.6kPa, Tair=28.2C, Tdew=12.8C
Zero Air at 1700psi, God Air 421.22 at 400 Tdewspan=16.00
CO2 zero 0.9392 -> 0.9392 Offset: 0.11ppm
CO2 span 1.012 -> 1.0131 Offset: 0.57ppm
H2O zero 0.9039 -> 0.9041 Offset: 1.0ppm
H2O span 1.0054 -> 1.0063 Offset: .01ppm
Notes: This sensor has been upgraded to firmware version 8.5.0. I connected it to Licor box sn AIU-0674 and used software version 8.5.0 to calibrate this sensor in order to calibrate the temperature coefficients (these coefficients are not calibrated in software version 8.0.0).
2617 2017-02-13 Factory Returned Lab none Returned from Licor after repair on 7550 box and calibration.
2616 2017-01-30 Lab none Calibration Lab none Last calibration: 2016-12-23
AGC= SDM= DAC1= DAC2=
Ambient P=kPa, Tair=C, Tdew=C
at psi, Licor CO2 at 749 Tdewspan=12
CO2 zero 0.9378 -> 0.9392 Offset: ppm
CO2 span 1 -> 1.0120 Offset: ppm
H2O zero 0.9006 -> 0.9039 Offset: ppm
H2O span 0.9663 -> 1.0054 Offset: ppm
Notes: Factory calibration after repair of 7550 box and upgrade to embedded software v8.5.0
2578 2017-01-05 Lab none Shipped Factory Sent to Licor on RMA 00199505 with AIU-0674. This head was on the box when its door was left open in the field and got rain inside. Subsequent lab calibration looked a little funny so it was sent with the box to Licor for a check.
2563 2016-12-23 Lab none Calibration Lab none Last calibration: 2016-12-06
AGC=102.2 SDM=6 DAC1=- DAC2=-
Ambient P=99.57kPa, Tair=14.95C, Tdew=C
Zero Air at 300psi, God CO2 421.22 at 400 Tdewspan=14.00
CO2 zero 0.9385 -> 0.9378 Offset: -2.65ppm
CO2 span 1.0171 -> 1.0000 Offset: 9.43ppm
H2O zero 0.9017 -> 0.9006 Offset: -7.5ppm
H2O span 1.0841 -> 0.9663 Offset: 2.45ppm
Notes: Recal after box failed in the field after getting rain inside because the door was left open. Pressure about 0.5kPa low. Large offsets. Waves with 1 to 2 min period in data at steady state. Sending to licor for check.
2560 2016-12-21 Twitchell Alfalfa Gas Analyzer CO2/H2O Removed Lab none This head was deployed with LI7550 box sn AIU-0674 when the box was damaged in the field. Could not determine in the field if the head was working so brought it back to the lab for testing.
2537 2016-12-06 Lab none Installed Twitchell Alfalfa Gas Analyzer CO2/H2O Installed on the Twitchell Alfalfa tower to replace sn 75H-2182 for calibration
2529 2016-12-06 Lab none Calibration Lab none Last calibration: 2016-05-20
AGC=103.3 SDM=6 DAC1= DAC2=
Ambient P=100.29kPa, Tair=15.36C, Tdew=3.00C
Zero Air at 350psi, God CO2 421.22 at 400 Tdewspan=16.02
CO2 zero 0.9385 -> 0.9385 Offset: 0.0ppm
CO2 span 1.0136 -> 1.0171 Offset: -1.92ppm
H2O zero 0.8969 -> 0.9017 Offset: 30.2ppm
H2O span 1.0146 -> 1.0841 Offset: -1.41ppm
Notes:
2474 2016-09-29 Sherman Wetland Gas Analyzer CO2/H2O Removed Lab none Removed from the Sherman Wetland tower for calibration. Replaced by sn 1594.
2284 2016-05-24 Lab none Installed Sherman Wetland Gas Analyzer CO2/H2O Installed on the Sherman Wetland tower at the initial set up of the site.
2277 2016-05-20 Lab none Upgrade Lab none Upgraded embedded software from 7.5.0 to 8.0.0
2275 2016-05-20 Lab none Calibration Lab none Last calibration: 2015-07-22 (Factory)
AGC=100.22 SDM= DAC1= DAC2=
Ambient P=100.03kPa, Tair=21.23C, Tdew=9.06C
Zero Air at 600psi, NOAA "Good Co2" 421.22 at 500 Tdewspan=15.09
CO2 zero 0.9380 -> 0.9385 Offset: 1.79ppm
CO2 span 1.0021 -> 1.0136 Offset: 6.22ppm
H2O zero 0.8966 -> 0.8969 Offset: 1.4ppm
H2O span 1.0037 -> 1.0146 Offset: 0.23ppm
Notes: Upgraded from 7.5.0 to 8.0.0 embedded software. Last calibration was Factory - all setting from Factory cal were saved. Factory cal done at 749.7 ppm and 11.98 degC.