Rae UltraRAE 3000, User Manual

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UltraRAE 3000 User’s Guide
22.7.7 Time
The Time is expressed as Hours/Minutes/Seconds, with two digits for
each. The time is in 24-hour (military) format.
1. Press [Y/+] and the display shows the current time. Note that
the left-most digit flashes to indicate it is selected.
2. Press [Y/+] to step through all 10 numerals (0 to 9).
3. Press [N/-] to advance to the next digit. The next digit to the
right flashes.
Repeat this process until all six digits of the new time are
entered.
Press [MODE] to exit.
•
Press [Y/+] to save the new date.
•
Press [N/-] to undo the change and move to the next sub-
menu.
22.7.8 Duty Cycle
The pump’s duty cycle is the ratio of its on time to off time. The duty
cycle ranges from 50% to 100% (always on; this is the default value),
and the period is 10 seconds. Therefore, a duty cycle of 60% means that
the pump is on for 6 seconds and off for four seconds. Duty cycling is
employed by the instrument to clean the PID. A lower duty cycle has a
greater effect on keeping the PID clean than a higher duty cycle.
Important!
Pump duty cycling is interrupted when the instrument
senses a gas. The pump’s duty cycle is disabled when the
measurement is greater than the 2ppm threshold and is re-enabled
when the reading falls below 90% of the threshold (1.8 ppm).
1.
Press [Y/+] to increase the value.
2. When you have completed your selection, press [MODE].
•
Press [Y/+] to save the new duty cycle value.
•
Press [N/-] to undo the change and move to the next sub-
menu.
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