28
AO2000-LS25
LASER ANALYZERS | OI/AO2000-LS25-EN REV. D
4
Design and function
Device description
A
Device components
B
Block diagram of the device electronics
1
Transmitter unit
2
Receiver unit
3
Power supply
4
Ethernet module (Transmitter unit)
5
Mainboard (Transmitter unit)
6
CPU module (Transmitter unit)
7
Analog input for external pressure and temperature sensors (Transmitter
unit)
Figure 9: Overview of AO2000-LS25
The transmitter unit consists of the laser module with
temperature stabilized diode laser, the collimating optics and
the electronics in a coated aluminum housing.
The receiver unit consists of a focusing lens, the photodetector
and the receiver electronics in a coated aluminum housing.
Transmitter and receiver units have housing protection IP 66.
The standard optical windows withstand pressures of up to
5 bar (absolute). The monitor is installed by assembling the
transmitter and receiver units with the supplied purging and
alignment units, which in turn are mounted onto the DN50
process flanges, see
on page 36.
The optical alignment is easy and reliable. The purging prevents
dust and other contamination from settling on the optical
windows.
The power supply unit transforms 85 to 264 V AC to 24 V DC (if
24 V DC is available the transmitter can be connected directly).
The power supply box is connected to the transmitter unit with a
cable.
The 4 to 20 mA input signals from the external temperature
and / or pressure sensors are connected in the plug housing of
the 24 V supply or, for Ex versions, to the screw terminals in the
terminal box of the transmitter unit.
The receiver electronics is connected with the transmitter
electronics with a cable. The detected absorption signal from
the photodetector is amplified and transferred to the
transmitter unit through this cable. The same cable transfers the
required power from the transmitter unit to the receiver unit.
The aluminum housing of the transmitter unit contains the
primary part of the electronics. The CPU board performs all
device control and calculation of the gas concentration.
