LaserGasTM II Dual Path Monitor
The Dual Path monitor is designed
for in-situ measurements with path lengths in the range 0.5 - 15 m (pipes,
stacks, ducts). Pressure and temperature ranges and available gases (see Table of
Gases) are as for the Single Path monitor.
The Dual Path monitor includes the additional feature of automatic zero and
span check, which is a requirement for certain emission monitoring
applications. Based on the well-proven tuneable diode laser (TDLAS) technology
the instrument has a number of unique features.
Features
- Response time down to one second
- No cross interference from other gases
- No gas sampling - in-situ measurement
- Very low detection limits (ppb and low
ppm)
- Wide range of process conditions
possible
- Suitable for high dust environments
- Low cost of ownership
- Ethernet connection (optional)
- Automatic zero and span check
The monitor consists of a
transceiver and retro-reflector unit, which are both suitable for outdoor use.
Measurement readings are provided through standard 4-20mA current loops, a
fibre-optic output or the optional Ethernet interface. The latter enables
communication via a local area network or the Internet.
Measuring
principle
LaserGas II monitors employ the
measurement principle known as 'single line spectroscopy', which eliminates
cross interference from other gases. A single gas absorption line with no
interference is chosen in the near IR spectral range and scanned by a
single-mode diode laser. A retro-reflector located opposite to the laser
reflects the light back to the transceiver. A detector collects the returned
light for further analysis and calculation of the gas concentration (see Technology for
more information).
Installation
and Operation
The LaserGas II DP monitor is easy
to install and designed to operate in very rough industrial environments. The
transceiver and retro-reflector units are mounted directly onto the duct or
stack flanges. Preventive maintenance is limited to visual inspection and
cleaning of optical windows. Purging with instrument air or nitrogen prevents
dust from fouling the optical windows. Calibration checks are recommended every
6 - 12 months.
Zero and Span
Check Operation
Refer to LaserGas I Dual
Path for a description.
Data sheet for
download
Not yet available.