Ametek Land 4200, Руководство пользователя

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User Guide Model 4200 Dust & Opacity Monitor
4.1.2 Retro-reflector
The retro-reflector is a small passive unit enclosing to IP65/NEMA4 specifications
a removable reflector (especially easy to clean). The reflecting surface uses
embedded corner cube technology. This technology is specifically designed to
reflect the beam of light directly back along the line of transmission with a
very large tolerance factor to whatever angle the light beam is received. A light
restrictive aperture is factory selected to suit the path length required by the
customer making it unnecessary for any further correction on site. A pair of
alignment sighting aids are also contained within the unit.
4.1.3 Transmissometer Weather Cover (optional)
A fibre glass weather cover (option) can be provided that will give added
protection to the transmissometer from the environment.
4.1.4 Auto Failsafe Shutters (optional)
Both the transmissometer and the retro-reflector can be further protected from
air supply failure to the air purges by the automatic failsafe shutter option. The
shutter responds instantly to any failure of air supply fan unit air mover and will
automatically shield the instruments delicate optics from the immediate ingress of
dust and gases that would occur.
Note
The automatic failsafe shutter (when operated) should not be relied upon
as a permanent means of protection but as a temporary protection until
the problem is rectified.
Air blowers/Airmovers should be operational at all times when the instrument is
mounted on the stack, otherwise damage to the system may occur.
4.1.5 Calibration Filters (optional)
Two calibration filters (options) can be supplied for use in conjunction with
manual calibration checks and/or calibration audits for linearity checks.