Field Notes

<--2004-12-01 10:00:00 | 2004-12-10 10:00:00-->
Other sites visited today: Vaira

Tonzi: 2004-12-09 09:00:00 (DOY 344)
Author: Ted Hehn
Others:

Summary: re-installed LI-800 in Tower co2 profile, Tower computer not running - power problems, soil CO2 profile problems

When: Wed-Thurs 9Dec04 JD-322
Where: Tonzi Ranch
Who: Ted Hehn
Weather â€“ Recent rains, cool and clear

Trip Purpose Install LI800

Tonzi Ranch:
09:00 arrive
Tower VDAC (Moe) was in protection mode and not running. Appears to have turned off at 05:00 yesterday and was not reset this morning at 05:00.

Inspection of the data indicate that the VDAC shuts down at 05:00 and does not power up until 7:30. This is due to the voltage depletion during dark periods and the voltage drop induced by the voltage regulator Ted built and installed. Similarly, when the system is powered up the inrush current also depletes the system voltage. The new regulators have a 5 second power on delay that should correct this situation.

Remove and reinstall power plug and Winfluxwmp begins running.

Install the LI800 sn AKC-0479. Reset the cal gas flow rates. Zero and span twice. OK all appears well. Note that a thermocouple was installed by gluing it externally on the sample cell inside the LI800. Similarly, a union T installed immediately on the output of the sample cell has a septum through which a thermocouple wire was inserted directly into the exiting sample stream.

Reset the tower watchdog timer to reset at 849 minutes and it functions perfectly.

There is a problem with the soil co2 profile system:
Soil CO2 profile system is showing southern sensors 1, 2, & 3 over-ranged and over-ranging data logger at 6.2 volts.

Probes digital readouts showing 1.4 - 1.8 % and these probes have a max span of 1%. Probe # 4 was showing 4500 ppm.

Field Data

No tank data

No TZ Well data found

No TZ Moisture Point data found

No VR Moisture Point data found

No TZ grass heigth found

No VR grass heigth found

No TZ Tree DBH found

No water potential data found

No TZ Grass Biomass data found

No TZ OakLeaves Biomass data found

No TZ PineNeedles Biomass data found