H3C Technologies H3C S3600 Series Switches - Handbuch (Seite 15)

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Fuse
For the safety of continuous operation, please replace the fuse with that of the same type and rating, if
necessary.
Laser
The laser hazard level of this equipment is Class 1.
When performing installation and maintenance operations of optical fibers, you should not stand close
to, or look into the optical fiber outlet directly with unaided eyes.
General Laser Information
Laser transceiver/ transmitter are used in optical transmission system and associated test instruments.
The wavelength of the laser is above 780nm, and lower than 1600nm. Because the laser being
transmitted through the optical fiber produces a small beam of light, it has very high power density and
is invisible to human eyes. When a beam of light enters the eye, retinal may be burned.
The damage mechanism at the wavelengths used in telecommunications is thermal in origin i.e.,
damage caused by heating. Therefore, a specific amount of energy is required for a definite time to heat
an area of retinal tissue.
Lasers used in lightwave systems have a larger beam divergence, typically 10 to 20 degrees.
Inadvertently viewing an un-terminated fiber or damaged fiber with the unaided eye at distances greater
than 150 mm (6 inches) will normally not cause eye injury. However, damage may occur if an optical
instrument such as a microscope, magnifying glass or eye loupe is used to view the energized fiber end.
In its normal operating mode, a lightwave system is totally enclosed and presents no risk of eye injury.
Additional safety is achieved by the implementation of an Automatic Laser Shut-down (ALS) of the
system. The ALS, however, can be applied for bi-directional transmission only. If the receiver side does
not detect the laser from the transmission side, it will give the transmission side a signal, so the ALS will
shutdown the laser emission in less than 100ms.
Laser Safety Guidelines
Read the following guidelines to avoid laser radiation:
z Read the relevant instructions before installation, operation and maintenance of the equipment.
Ignoring the instructions can cause in exposure to dangerous laser radiation.
z An eye-protective glasses are recommended when you are handling lasers or fibers.