Specifications

LI-7700 Open Path CH4 Gas Analyzer

Calibration Range: 0-40 ppm @ 25 °C

0-25 ppm @ -25 °C

0-50 ppm total

Bandwidth: 0, 1, 2, 5, 10, or 20 Hz

Linearity: Within 1% of reading across full calibration range

Resolution: 5 ppb (RMS @ 10 Hz, typical ambient levels)

Operating Temperature Range: -25 °C to 50 °C

Operating Pressure Range: 50 to 110 kPa

Relative Humidity Range: 0 to 100%

Detection Method: Wavelength Modulation Spectroscopy, 2f Detection

Data Communication: Ethernet

Data Inputs: 4 Analog Inputs (single ended, ±5 V, 16 bit), 3 type E thermocouple

Power Requirements: 10.5 to 30 VDC

Power Consumption: 8 watts nominally, up to 41 watts with accessories. See Table D‑1 for details.

Size: 14.33 cm (5.64 in) dia., 83 cm (32.7 in) height, 94.6 cm (37.25 in) height with mounting post

Weight: 5.2 kg (11.5 lbs.)

Optical Path: 0.5 m physical path length (1.65 ft), 30 m measurement path (98.4 ft)

Cable Length (Power and Data): 5 m (16.4 ft)

Class 1 Laser Product

7700-101 Washer Assembly

Power Requirements: 8 watts, see Table D‑1 for details.

Operating Temperature Range: -10 °C to 50 °C

Size: 44.5 x 32.8 x 15 cm (17.5 x 12.9 x 6 in) external dimensions

Weight: 3.2 kg (7 lbs)

Fluid Capacity: 4 L (1.1 U.S. gallons)

Maximum pumping height: 5 m above pump with provided tubing and nozzle

Cable Length: 5 m (16.4 ft)

Tube Length: 5 m (16.4 ft)

LI-7550 Analyzer Interface Unit (optional)

Data Storage: Removable USB Storage. 4 GB provided, (>1 TB max; expandable with user-supplied industrial grade USB Flash Drive)

Data Communication:

Ethernet

Synchronous Devices for Measurement: (33.3 Hz)

RS-232: (57,600 baud, 20 records per second)

6 Digital-to-Analog Converters: (0-5 V, 300 Hz)

Inputs: Ethernet, 4 Analog Inputs (differential, ±5 V, 16 bit)

Operating Temperature Range: -25 °C to 50 °C

Power Requirements: 10.5 to 30 VDC

Power Consumption: 10W nominally

Dimensions: 35 × 30 × 15 cm (13.8 × 12 × 6 in) external dimensions

Weight: 4.4 kg (10 lbs)

Cable Length (Power, Data, Analog Input/Output, Ethernet, and SDM): 5 m (16.4 ft)

LI-7550 dimensions (early versions)

LI-7550 dimensions (new versions)

7550-101 Auxiliary Sensor Interface (optional)

Size: 11.5 cm x 6.5 cm x 4.2 cm (4.5 in x 2.6 in x 1.7 in.)

Weight: 0.39 kg (0.85 lbs) including mounting bracket

Cable Length: 0.75 m (2.5 ft)

Power Requirements Summary

The LI-7700 uses about 8 watts during normal operation, but when accessories and mirror heaters are used, power requirements could be up to or greater than 41 watts. Table D‑1 can be used to determine how much power is required in a variety of configurations:

Table D‑1. Typical LI-7700 power requirements for a variety of configurations.
  CH4 Analyzer Washer Assembly Mirror Heaters LI-7550 Power Consumption
Upper Lower
Normal Operation (watts) 8         8
8       10 18
During Cleaning Cycle (watts)1 8 8       16
8 8     10 26
Mirror Heaters On (watts)2 8   0 to 7.5

 

   8 to 15.5
8

 

 0 to 7.5 0 to 7.5   8 to 23
8   0 to 7.5 0 to 7.5 10 18 to 33
8 8 0 to 7.5 0 to 7.5 10 26 to 41