LI-820 Frequently Asked Questions
Q What is the measurement range for the LI-820?
A The LI-820 measures CO2 ranging from 0 to 20,000 ppm.
Q What are the main differences between the LI-840A and the LI-820?
A The LI-840A measures both CO2 and H2O, whereas the LI-820 only measures CO2. Both instruments measure CO2 in the range from 0 to 20,000 ppm. LI-820 and LI-840A Comparison
Q Do I need a pump with my LI-820?
A An external pump is required for the LI-820. The pump should provide a flow rate between 0 and 1 liters per minute with this instrument. LI-COR offers a list of parts and alternative vendors that provide suitable pumps. Specifications for this and a list of parts and vendors can be found at: https://www.licor.com/documents/dmhq6ow23w2qgy3dsb8v.
Q How do I power my LI-820?
A Power can be supplied by a 10.5-30VDC input voltage. Batteries or an optional AC adapter (part number 800-401) can also be used to power the LI-820.
Q How often do I need to calibrate my LI-820?
A Factory calibration is not required for the LI-820. User zero and span checks are suggested at least once a month but can occur as often as desired. For the higher CO2 ranges, a two point span is required.
Q How can I log data with my LI-820?
A Data can be logged to a computer with the LI-820 software or to a data storage device using XML, analog outputs (0-2.5 V or 0-5 V), or current outputs (4-20 mA). The LI-1400 Data Logger or other data logger would be suitable.
Q Can the LI-820 send an alert if my CO2 levels are out of my desired range?
A The high and low alarms can be configured to activate if CO2 levels are outside of a desired range. The alarms are typically used to activate an electronic trigger, which could control exhaust fans in a greenhouse, automatic dialers, audible alarms, pumps, or valves in industrial applications.