Vaisala LM21 - Page 4

User's Guide ________________________________________________________
4 ______________________________________________________ M210283en-A
Communication Options..................................... 30
Microcontroller.................................................... 30
Input Protection.................................................. 30
Diagnostic and Supportive Circuits.................... 31
Optical Contamination and Blocking Monitoring. 31
Contamination Compensation............................ 32
Sensitivity Check................................................ 33
Heater Operation................................................ 33
CHAPTER 6
MAINTENANCE...................................................................... 35
Cleaning the Window ........................................... 35
Calibration Check and Calibration Procedure ... 37
Replacing the LMM101 Cover Frame Assembly 42
Replacing the LM211244 Cover Subassembly and
Cabling .................................................................. 45
Replacing the Measurement Board LMB201...... 49
CHAPTER 7
TROUBLESHOOTING............................................................ 51
Errors .................................................................... 51
Alarms ................................................................... 52
Indications ............................................................ 53
Miscellaneous Problems ..................................... 54
Getting Help.......................................................... 54
Return Instructions .............................................. 55
CHAPTER 8
TECHNICAL DATA................................................................. 57
Specifications....................................................... 57
Mechanical Specifications.................................. 57
Operational Specifications ................................. 58
Optical Specifications......................................... 58
Electrical Specifications ..................................... 58
Environmental Specifications ............................. 59
Electromagnetic Compatibility............................ 59
INDEX ..................................................................................... 61
List of Figures
Figure 1 LM21 Background Luminance Sensor ................... 14