Calibration Issues
Zeroing the Leaf Temperature Thermocouple
Using the LI-6400
18-19
Zeroing the Leaf Temperature Thermocouple
The only calibration required for the leaf temperature thermocouple is itÕs
zero adjustment. ItÕs a good idea to check this at the start of each day; not be-
cause it drifts that much, but because itÕs easy to do, and is part of good pre-
operation practice. After all, if you have a broken thermocouple, for example,
itÕs better to find out before you make your measurements than after.
1
Unplug the thermocouple connector
Remove the male thermocouple connector by pulling straight out.
2
Monitor TBlock and Tleaf
Configure the New Measurements screen so that you can view both the leaf
temperature and block temperature variables (
Tleaf ¡C
and
Tblock ¡C
, respec-
tively). In the default display configuration you can view these variables by
pressing
H
.
3
Make them read the same
There is a small adjustment screw located on the underside of the sensor head,
near the rear of the analyzer housing (Figure 18-11). Once the instrument has
been on for about 30 minutes to warm up, use the small flat head screwdriver
in the spares kit to turn the adjustment screw until the displayed leaf temper-
ature and block temperature match.
4
Reconnect the thermocouple connector.
Figure 18-11. Location of the leaf temperature zero adjustment screw.
Zero Adjust
Summary of Contents for LI-6400
Page 1: ...Using the LI 6400 Portable Photosynthesis System ...
Page 15: ...Part I The Basics ...
Page 16: ......
Page 174: ...Making Measurements Answers to Questions 4 56 Using the LI 6400 4 ...
Page 175: ...Part II Useful Details ...
Page 176: ......
Page 200: ...Standard Tools Power ON Hooks 5 24 Using the LI 6400 5 ...
Page 214: ...Real Time Data Real Time Graphics 6 14 Using the LI 6400 6 ...
Page 234: ...Environmental Control Light Control 7 20 Using the LI 6400 7 ...
Page 244: ...Light Sensor Considerations Gallium Arsenide Phosphide GaAsP Sensor 8 10 Using the LI 6400 8 ...
Page 288: ...Data Logging Making Your Own AutoPrograms 9 44 Using the LI 6400 9 ...
Page 289: ...Part III Working With Files ...
Page 290: ......
Page 312: ...The LPL File System Troubleshooting 10 22 Using the LI 6400 10 ...
Page 340: ...Downloading Files Using a Data Capture Program 11 28 Using the LI 6400 11 ...
Page 375: ...Part IV Configuration Issues ...
Page 376: ......
Page 420: ...Defining User Variables Old Style vs New Style 15 18 Using the LI 6400 15 ...
Page 454: ...Using an Energy Balance Further Reading 17 12 Using the LI 6400 17 ...
Page 455: ...Part V Maintenance Troubleshooting ...
Page 456: ......
Page 572: ...Troubleshooting Useful Information 20 46 Using the LI 6400 20 ...
Page 593: ...Part VI Programming ...
Page 594: ......
Page 622: ...Programming with LPL Compiler Directives 22 28 Using the LI 6400 22 ...
Page 846: ...Index I 16 Using the LI 6400 ...