OPENÕs System Variables
Status Variables
14-14
Using the LI-6400
14
ID: -28
ÒFLOWÓ
The flow control hardware can indicate four values:
A ÒHighÓ condition occurs when asking for unattainably high flow rates. The
obvious way to make this happen in fixed flow mode (F) is to enter a big tar-
get value, such as 2000. The more subtle way to make this happen is in the
constant humidity control mode when the target is too dry, and/or the incom-
ing air is too moist.
A ÒLowÓ condition occurs when asking for unattainably low flow rates. This
occurs most often when using the 6400-01 CO
2
Mixer, which means the flow
control is done with a diverter valve.
ID: -30
ÒFANÓ
The sample and leaf chamber cell mixing fan can have three values:
The fan is controlled by setting a DAC (channel 7) between 0 (off) and 5
(high) Volts. The setting for ÒLowÓ is defined by the configuration command
FanSlow=, and defaults to 4 volts.
Table 14-4.
Flow status
Value
Meaning
What is Sensed
0x0300
a
0x0103
b
0x0104
OK
Flow control in balance.
1
1
1
Low
CanÕt reduce flow low enough.
1
0
1
High
CanÕt raise flow high enough.
1
ignored
0
a.Pump control output, port 3 pin 0.
b.Digital input port 1, pins 3 and 4.
Table 14-5.
Fan status
Value
Meaning
What is Sensed
Off
Fan switched off
Voltage on DAC chan-
nel 7, the fan control.
Low
Fan at the Low voltage.
High
Fan at the High voltage.
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 ...