Troubleshooting
New Measurements Mode Warning Messages
20-8
Using the LI-6400
20
¥
Increase the flow rate.
This will reduce the chamber humidity.
¥
Dry the incoming air further
Increase the desiccant scrubbing.
¥
Water IRGA OK?
If the high humidity alert persists, perhaps the problem is with the water IR-
GA. Check itÕs zero and (if possible) span. Is it responsive? (If the readings
donÕt seem to change, then the analyzer board fuse may be blown (page
19-10); this can happen without causing the IRGAs Not Ready message.)
ÒChamber Fan is OffÓ
This message refers to the internal fan in the sample cell, which is controlled
via function key
f3
(level 3), labelled
FAN
. Note that the instrument cannot
sense if the fan is actually moving or not; the message is a response to the
switch (digital output) setting. The only way to tell if the fan is functioning is
to turn it on and off and listen for sound changes.
ÒPump is OffÓ
If the pump is off (accomplished by selecting ÒNoneÓ in the Flow Control Op-
tions (
2 F2 N
)), this message will appear. The software senses the pumpÕs
status by checking the digital output that controls it. If the pump is in fact not
operating due to other reasons (not being plugged in, blown fuse, etc.), it will
not
cause this message to appear.
ÒFlow is Too LowÓ
The minimum recommended flow is 50 µmol s
-1
with a 6400-01 Mixer, or
100 without. In fixed flow mode, if the flow drops below this value, the ÒFlow
is Too LowÓ message will appear. Note that if OPEN is in any other flow con-
trol mode, flow rates less than this are tolerated (since the system is control-
ling flow rates, and not the user), and this message will not appear.
If ÒFlow is Too LowÓ appears even though the
requested
flow rate is higher
than 50 µmol s
-1
, check for a blown flow board fuse; the
real
flow may be 0
because the pump is not running. If the flow board fuse has failed, a number
of other things will not be functioning as well, such as the console cooling
fan, light source, light source fan, cooling fans, chamber fan, and CO
2
injec-
tor.
ÒFLOW: Need
-
SCRUB or wetter targetÓ
The Ò
-
SCRUBÓ
refers to the desiccant tube adjustment label, and the direction
you may wish to turn the knob. Specifically, this message means that the tar-
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 ...