Crowcon Tetra MO7237, User Manual, Page: 15 / 36

Tetra Logging
Peak test
When performing a peak test, such as a vertical entry check, previous
readings can be cleared on entry to the peak display option.
Zero
The Tetra instrument can perform an autozero by selecting the Zero
function from the menu. When zero is completed, the instrument will
return to normal operation.
2.5 Logging
Tetra incorporates data and event logging which can be accessed using the IR
communications link with Portables PC software (See section VIII). It can record
data each minute for 50 hours up to a limit of 1500 events.
Tetra records the time and date for a number of operating and diagnostic
events including:
• Switch on and switch off
• Level 1, Level 2 and Time Weighted Average Alarms, alarm on,
alarm off and the peak level during the alarm
• Zero, calibration and gas test with success or failure
• Pellistor saver on and off
• The battery condition is logged every 15 minutes while the
instrument is operating, and certain configuration changes are
also logged.