HDP Notes 11-08-16 cal gases run out in early August (turned off program). 11-04-11 C.S. visited site and replaced downstream Nafion (previous had a big leak that had slowed over time) - system now leaking at ~ 0.15 ------------------------------ 2010: 10-12-13 on 9 Dec 2010 /data became "read-only". No data saved between 12/9-12/13. remounted /data in "rw" mode. collecting data again (SpB). 10-11-17 to 10-11-18, trip to HDP to swap cal gases and fix several issues with the aircoa. collecting data again (BBS) 10-09-17 All 4 cal gases ran out within the past two weeks. Stopped program and commented out last line in rc.sysinit (SpB). ------------------------------ 2009: 09-10-23, Dave Bowling swaps the 4 cal gas cylinders (empties left at HDP). AIRCOA program re-started. 09-09-23 Three cal gases ran out this week. Stopped program and commented last line in rc.sysinit to preserve last gas. 09-09-17 Comms back up and data collecting 09-08-21 Network communications were down until Sept. 17, but appears to have filled memory drive on Aug. 21 09-06-03 Sean found /data not mounted again (had rebooted on 090601). Fixed. 09-05-25 Noticed /data was not mounted. remounted and restarted aircoa program. Also fixed time from: Mon May 25 21:28:59 2009 to Mon May 25 21:57:02 2009 (old time was approx 20-30 minutes slow). (SpB). 09-05-24 Time was slow by ~ 27 min 30 sec, attempted to fix manually at 22:15:30 and rebooted. Reset to 27:45 (mm:ss) slow. 09-05-18 to 09-09-24 Transients/offsets/slopes got slowly better, by mid-July: HS2 up/down = + 1/0 ppm HS1 up/down = + 0.6/0.6 ppm LS1 up/down = + 0.3/1.0 ppm LS2 up/down = + 0/1 ppm Sample after cal/LT/Cal slopes = -0.8/-1.6/0.20 ppm/min HDP-SPL = 2 ppm LT-assigned = 5.5 ppm and by Sept. 19: HS2 up/down = + 0.2/0 ppm HS1 up/down = + 0/0 ppm LS1 up/down = + 0/0.3 ppm LS2 up/down = + 0/0 ppm Sample after cal/LT/Cal slopes = >-0.5/-0.7/0.11 ppm/min HDP-SPL = 0 ppm LT-assigned = 2.3 ppm Also, T sensitivity down to -0.15 ppm/C Disc: CO2 slopes same for first sample or LT, affects cal and sample (in opposite directions) so downstream of manifold, CO2 offset for sample does not depend on cal so not a x-port leak, most likely a residual water effect downstream of manifold responding to P swing, RH does not show slopes so either not sensitive enough or prob is surface not dilution related. LT is still affected, because it follows low-P leak check. Cal-Sample pressure diff = 0.05 kPa, LowP-LT pressure diff = -0.45 kPa but slopes for Sample and LT are in the same direction. Difference may be partly associated with upstream Nafion and it cares whether it is seeing wet or dry air - e.g. when dry LT hits Nafion, a bunch of CO2 is released and then it slowly gets better. Switch to cal gas may be in same direction but with quicker recovery and then overshoot, giving positive slope. Switch to sample looks same as LT too - difference is Cal changes direction. Shotened averaging periods for 5/19 - 9/24, but did not seem to change 4-pt vs. individual cal differences or HDP-SPL differences. 09-05-18 After running fine for three days, spikes/slopes started - spikes are after cal-sample switch, worse when following FullCal2 (down+lkchks), better when following FullCal1 (up+LT), but dir/mag not dependent on gas (suggest pressure effect instead of x-port leak). Cals have a high T variability (-0.3 instead of -0.08 ppm/C) and 4-pt cals are higher than individual cals: HS2 up/down = + 3.5/0 ppm HS1 up/down = + 2.5/2 ppm LS1 up/down = + 1.5/3 ppm LS2 up/down = + 0/3 ppm Sample after cal/LT/Cal slopes = -5/-6/0.94 ppm/min Measured CO2 and LT are still ~ 10 ppm (HDP-SPL) high after transients have settled. By the end of the month CO2 and LT only ~ 5 ppm high and 4pt-1pt cal offsets down by factor 2: HS2 up/down = + 1.5/0 ppm HS1 up/down = + 1/1 ppm LS1 up/down = + 0.5/1.5 ppm LS2 up/down = + 0/1.5 ppm And slopes down even more: Sample after cal/LT/Cal slopes = -1.5/-3/0.32 ppm/min 09-05-18 Attempted to manually correct time offset (5-10 min fast?). Later learned that correction reset to ~ 27 minutes slow after rebooting. Old time 22:48, new time around 22:22. On 14th, RH started out positive but quickly drifted to -15. On 18th, after this reboot it jumped to -10 (around 4 hours after CO2 problems appeared), and jumped again after a power outage around 2 weeks later. 09-05-14 Replaced LI-820 (new= S/N CGA-752), replaced both Nafion tubes (water in old tubes). Replaced T/RH humittor. Replaced MFM for line 3. Transported four new calibration cylinders up to the site (left near cylinders that are currently running). Restarted program. NTP not working. (AW, SpB). 09-05-09 Turned back on in anticipation of visit, but flow still low ------------------------------ 2008: 08-09-01 Appears to have ingested liquid water during intense storm ~ 5:30 AM UTC. Some components recovered, but flow low, V6 leaks, and Li820 cal off. Stopped program and commented out line in rc.sysinit 08-09-08. 08-08-28 NTP still not working. 5:05 slow. Set manually at 20:43:30 08-07-15 Found NTP was not working. 68 Sec slow. Set manually 08-02-23/24 Replaced 4 calibration cylinders. Replaced Li-820 (new = S/N CGA-689), mole-seives, and humitter. Replaced line 2 and 3 5 um line filters and rebuilt inlet manifold to put filters upstream of needle-valves. Replaced inlet filters and repositioned 17.7 m inlet. Swapped lines 2 and 3 back to original configuration (line 3 = 17.7 m west inlet). 08-01-25 Both HS2 and LS2 appear to have run out. Stopped program on 08-01-30. ------------------------------ 2007: 07-12-16 Memory stick filled up. Cleared and rebooted on 07-12-18. Somehow pen drive did not mount. Manually mounted and restarted program on 07-12-19. 07-07-18 D. Bowling replaced pump, tuned up. Humitter appears to have intermittent connection problem. 07-07-10 Micropump failed. Stopped program on 7/11 07-03-07 B. Stephens on site. Replaced 4 calibration cylinders. Replaced air select solenoid (6) which fixed a leak. Switched lines 2 and 3 at bulkheads to diagnose offset. Fixed settings2.txt to go to line 2 instead of line 1 during cals. 07-02-04 G. Poulous onsite. Breath test and outer line connections tightened. ------------------------------ 2006: 06-12-24 Low P leak check suddenly jumps to -0.25 kPa/min. 06-10-11 HDP site visit. Replaced "Air" solenoid to fix leak. Zero and span on LI820. Tuned up. 06-10-11 Updated code to new version (lll) in anticipation of switching flow meter wires. RH jumped ~ 0.65. 06-09-25 High pressure leak rate suddenly jumps from -0.09 kPa/min to -2.2 kPa/min. No known visitors. 06-08-22 00:21 changed settings to purge nafion with line 2 during low pressure leak checks instead of line 1 06-07-12 S. Schaeffer returns, replaces Bev-a-line to micropump. Leak rate drops to ~0.1 kPa/min. Communication restored. 06-07-06 S. Schaeffer visits to fix high pressure leak check. Replaces broken fitting but leak still present. Leaves unit on, but communications appears to have failed. 06-04-19 and 20 Installed AIRCOA E with two inlet lines. Fixed positive pressure leak (0.2 kPa/min), but it returned several hours after leaving site.