Introduction to the LI-7815

The LI-7815 CO2/H2O Trace Gas Analyzer is a high-precision, high-stability, laser-based gas analyzer that uses Optical Feedback — Cavity-Enhanced Absorption Spectroscopy (OF-CEAS) to measure gases in air. OF-CEAS is a well-established spectroscopic technique that is described in published literature. The analyzer reports and stores in its internal memory CO2 dry mole fractions in air corrected for both the spectroscopic interferences and dilution due to H2O. See Measurement overview for a brief summary of OF-CEAS.

What's what

If you have just taken delivery of the instrument, check your packing list to be sure you received everything that you ordered. The LI-7815 includes some or all of the following components.

Gas analyzer

The gas analyzer is in a gray enclosure. It is designed for indoor and outdoor use but it is not waterproof.

The analyzer should not be allowed to sit in standing water, exposed to driving rain, or deployed outdoors without weather protection. Use caution to avoid drawing water into the analyzer air inlet! Although equipped with software protection that disables the pump if a clog is detected (such as the filter becoming wet and stopping air flow), if water is drawn into the inlet the instrument will have to be repaired at the factory.

Power button

The power button is used to power the instrument on and off and enter and exit sleep mode. It has an indicator light that will be illuminated when the instrument is powered on and dark when it is powered off. Functions of the button are described in Powering on the instrument and Powering off the instrument.

Power cable connector

The power cable connector on the instrument is compatible with the universal power adapter (part number 9968-232) and the optional DC power cable (part number 9968-242). See Power options.

Warning: Use the safety-approved power cord supplied with the instrument. The instrument power supply is equipped with a 3-wire grounding plug. This plug will only fit into a grounded outlet. Do not defeat the purpose of the grounding-type plug. Do not place the instrument where the power cord will be walked on or exposed to water or chemical spills.

Network cable connector

The network cable connector is compatible with standard RJ-45 Ethernet cables.

Air inlet

The instrument draws air in through the inlet using the internal pump. The inlet connector is a compression fitting, which is compatible with ¼" outside diameter tubes. Additional nuts and ferrule sets are include in the accessories kit.

Warning: Do not exceed the maximum absolute pressure rating of 110 kPa.

Air outlet

The instrument exhausts sample air through the outlet. Do not substantially restrict or apply a vacuum to the outlet.

Rechargeable batteries

Part Number 442-11807

Two batteries are provided with the instrument. We recommend leaving at least one battery in the instrument when you are using it. The batteries are 14.4 V lithium ion battery packs with 6.8 amp-hour capacity. Two batteries can provide up to 8 hours of operation under most conditions. Batteries are shipped in a partially discharged state. They should be fully charged prior to the first use. Storing the batteries in a discharged state can result in damage to the batteries. Batteries that are installed in the instrument will be charged when the instrument is powered though the universal power adapter.

Warning: Lithium ion batteries may cause environmental damage or damage to human health if they are disposed of improperly. Do not dispose of the batteries in unsorted municipal waste or an incinerator. Many localities have battery recycling facilities that will accept lithium ion batteries. Check your local regulations to determine how to safely dispose of the batteries.

Universal power adapter

Part Number 9968-232

The universal power adapter is an AC-to-DC adapter that powers the instrument and charges the batteries when it is plugged into an AC power outlet. The power adapter provides 24 VDC (9.17 amps maximum; 220 watts maximum). It is compatible with 100 to 240 VAC, 50 to 60 Hz. The instrument will include one of the cords listed in Table 1. The power adapter and cord are for indoor use; they are not rated for outdoor deployment.

Table 1. Power cables for the power adapter.
Description Part Number
For USA, Canada, Mexico, and Japan; NEMA 5-15; Type B 390-00787
For Europe, South America, and Asia; CEE 7/7; Type C 390-01486
For United Kingdom; Type G 390-03089
For Israel; SI32; Type H 390-03059
For Australia; Type I 390-03095

Warning: Use the safety-approved power cord supplied with the instrument. The instrument power supply is equipped with a 3-wire grounding plug. This plug will only fit into a grounded outlet. Do not defeat the purpose of the grounding-type plug. Do not place the instrument where the power cord will be walked on or exposed to water or chemical spills.

Ethernet cable

Part Number 616-06116

Network cable with RJ-45 connectors (Cat5e); to connect the instrument to a computer or network. Length of 2.1 meters (7 feet).

Note: Do not use cables other than the one provided. Other cables may result in improper electrical performance.

Accessory kit

Part Number 9978-195

The accessory kit includes some accessories and replacement components that may be useful to you. Additional replacement parts are available from LI-COR or your local distributor.

Description Quantity Part Number
Replacement dry-down chemical pack (17 grams each) 3 622-17627
Stainless Steel Screws ; M3×0.5; 8 mm 6 150-14419
O-ring; 27×1.5 mm 2 192-16956
O-ring; 22×2.5 mm 4 192-17345
Stainless Steel 1/4" Ferrule and Nut Set 5 300-15025
Filter support disks 2 9878-280
Filter pack; 2-micron (10 filters) 1 9978-234

Optional accessories

In addition to the items already mentioned, the analyzer may include the following accessories.

Auxiliary power cable

Part Number 9968-242

This optional component allows you to power the instrument from an external DC power supply, such as a deep cycle battery. It has a connector for the instrument power connection and bare leads for a power source. Power requirements are given in External power source.

Backpack kit

Part Number 6578-380

The backpack kit is an optional accessory that can be used to carry the instrument. It features a padded back and padded shoulder straps with a padded waist strap and chest strap to help support the instrument as you carry it.

The analyzer is secured in the backpack with several straps. The bottom of the instrument will be against your back. The tubes can face up or down. Use caution with the backpack kit:

  • Close the clasps and tighten the straps so that the instrument is secure.
  • Do not block the vents or set the instrument in standing water.
  • If you are unable to lift the backpack kit comfortably or tighten the straps, consider enlisting the help of a "strapping" assistant.
  • Clip the chest and waist straps. Tighten all of the straps snugly.