Vaisala LT31, Руководство пользователя

Страница: 139 / 294

Chapter 4 _______________________________________________________________ Installation
VAISALA ______________________________________________________________________ 139
NOTE Use the CLOSE command after the configuration and operation check
is finalized.
Final Alignment
During the assembly as explained in Chapter 4, Installation on page 67,
the LT31 receiver and transmitter have already been roughly aligned in
relation to each other. To optimize this alignment, an acoustically
supported, menu-guided, automatic fine-alignment is a standard LT31
procedure.
CAUTION
Final alignment must be carried out at this point of the LT31
installation.
For details on the final alignment, see section Alignment on page 225.
NOTE Always select Raw and Fine Alignment mode for the final alignment
during installation.
Calibration
As the achievable measurement signal depends on the individual
tolerances of the opto-electronic systems and the alignment result itself,
the measurement signal has to be correlated to the prevailing visibility to
bring the Transmissometer into a final operational condition. This
process is carried out in the frame of the LT31 Calibration. The LT31
Calibration Procedure is menu-guided.
CAUTION Calibration must be carried out at this point of the LT31 installation. A
sufficient fine-alignment quality is required in any case.
To do the calibration, follow the instructions in section Calibration on
page 232.
NOTE Always select the Base Calibration mode for the initial calibration
during installation.