YASKAWA SIEMENS CNC Series, Maintenance Manual, Serviceman Handbook

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Safety precautions
xvi
• Observe the following when designing or installing enclosures (a poorly
designed or installed enclosure for a high-voltage unit could result in dam-
age or malfunction):
• The enclosures must be of hermetic seal type.
• The average temperature rise of the product must be not more than 10
℃
.
• Air stirring fans must be installed within the enclosures to improve cooling
efficiency and prevent local heat buildup (fans should be UL certified).
• Sealing to close cable inlet holes and doors must be effective.
• Displays tend to collect airborne dust and thus malfunction. Therefore their
enclosures must be so designed as to prevent dust intrusion.
• CNC and other units as well as PC boards could malfunction due to accumu-
lated dust. Therefore their enclosures must be so designed as to prevent dust
intrusion.
• Packing must be provided so that cable inlet holes, doors, and back plates are
fully closed.
• Observe the following when installing the units (poorly installed units could
result in damage or malfunction):
• The servo units must be fixed upright using screws or bolts.
• The servo units must be provided with enough space over and under them to
allow them to effectively dissipate their heat.
• Install a servo unit in an enclosure such that the heat sink fins of the unit come
out of the enclosure to keep the unit’s internal temperature lower. The exposed
heat sink fins must be subjected to a 2.5 m/s air draft.
• If an air stirring fan is installed inside an enclosure, the fan must be oriented
such that the air does not directly hit a servo unit (to prevent the servo unit
from collecting more dust).
• Units must be installed such that inspection, replacement and other servicing
activities are easy.
• Do not operate the system if any inverter or converter is physically broken
or otherwise damaged.
Otherwise injury could result.
• When handling the units, hold them by the mounting base, not by the front
cover.
If you hold them by the front cover, the main body could come off the front cover
and might drop onto and injure your foot.
Mount the units to a metal or other non-flammable structure. Otherwise, a fire
could result.
• The maximum operating temperature of 55
℃
must not be exceeded. The
air draft hitting the heat sink must be at not more than 45
℃
.
Note that overheat could result in a burn or a fire.
• An external emergency stop circuit must be provided so that operation
can be stopped and power shut off immediately.
Be aware of a risk of injury.
CAUTION