Troubleshooting
Real Time Clock Problems
20-6
Using the LI-6400
20
Real Time Clock Problems
DoesnÕt Keep Time When Power Off
The first thing to check is the clockÕs battery (Figure 20-1). Measure its volt-
age relative to Test Point 10; it should be 2.7V or greater.
The battery (LI-COR part number 442-03791) is a ÒcoinÓ type, and is held in
place in a holder on the corner of the board. It is easily removed, but be sure
the instrument is powered off, lest you short the test points right in front of
the battery holder and blow a fuse.
If the batteryÕs life seemed unexpectedly short (it should be several years),
then the battery may draining because capacitor C3 is leaky. If C3 is leaky
enough, it can even prevent the clock from running while the instrument is
turned on (next section).
ÒClock StoppedÓ Message
OpenÕs main screen displays the time and date, which should update each sec-
ond. If the real time clock is not running, the message ÒClock StoppedÓ is dis-
played instead. If this happens, and the SET CLOCK program
(
on page 21-18) doesnÕt fix it, then you very likely have a
leaky capacitor C3. If you canÕt test or replace it, you might try cutting one
leg off to disable it. If C3 is the problem, disabling it will allow the clock to
run while the instrument is powered off, but youÕll have to set the time each
time you turn it off until C3 is replaced.
Clock battery
C3
TP10
Figure 20-1. Location of the clock battery, Test Point 10, and capacitor C3.
Содержание LI-6400
Страница 1: ...Using the LI 6400 Portable Photosynthesis System ...
Страница 15: ...Part I The Basics ...
Страница 16: ......
Страница 174: ...Making Measurements Answers to Questions 4 56 Using the LI 6400 4 ...
Страница 175: ...Part II Useful Details ...
Страница 176: ......
Страница 200: ...Standard Tools Power ON Hooks 5 24 Using the LI 6400 5 ...
Страница 214: ...Real Time Data Real Time Graphics 6 14 Using the LI 6400 6 ...
Страница 234: ...Environmental Control Light Control 7 20 Using the LI 6400 7 ...
Страница 244: ...Light Sensor Considerations Gallium Arsenide Phosphide GaAsP Sensor 8 10 Using the LI 6400 8 ...
Страница 288: ...Data Logging Making Your Own AutoPrograms 9 44 Using the LI 6400 9 ...
Страница 289: ...Part III Working With Files ...
Страница 290: ......
Страница 312: ...The LPL File System Troubleshooting 10 22 Using the LI 6400 10 ...
Страница 340: ...Downloading Files Using a Data Capture Program 11 28 Using the LI 6400 11 ...
Страница 375: ...Part IV Configuration Issues ...
Страница 376: ......
Страница 420: ...Defining User Variables Old Style vs New Style 15 18 Using the LI 6400 15 ...
Страница 454: ...Using an Energy Balance Further Reading 17 12 Using the LI 6400 17 ...
Страница 455: ...Part V Maintenance Troubleshooting ...
Страница 456: ......
Страница 572: ...Troubleshooting Useful Information 20 46 Using the LI 6400 20 ...
Страница 587: ...Diagnostics and Utilities Sys Utility Programs Using the LI 6400 21 15 EBVpd t C guess EBSatVap _EBvap_kPa ...
Страница 593: ...Part VI Programming ...
Страница 594: ......
Страница 622: ...Programming with LPL Compiler Directives 22 28 Using the LI 6400 22 ...
Страница 846: ...Index I 16 Using the LI 6400 ...