Siemens YASKAWA 840DI Maintenance Manual page 13

• Never apply an AC three-phase power to the U, V, and W output terminals on a
Drive Unit powering a motor.
Otherwise the Drive Unit would be damaged.
• The capacity and wiring size of customer's power supply must be so selected as
to satisfy the specific operating conditions and required capacity. Note that the
actual capacity of a cable decreases significantly if the ambient temperature
exceeds 30 °C. Determine a correct cable size according to applicable electrical
installation regulations and the technical specifications issued by the cable
manufacturer.
Use of a cable of incorrect size could result in a fire.
• Signal cables must be of twist pair, twist-pair multi-strand, or shielded twist-pair
multi-strand type. If a type is specified for signal cables in this manual, that type
must always be used.
Otherwise malfunction could result.
• Cables must be so routed as to be as short as possible.
Otherwise malfunction could result.
• Input or output signal cables must not be bundled together with power cables or
routed in the same wiring duct with power cables inside or outside the panels.
Properly separating signal cables from power cables reduces the effect of electric noise
from the power cables on the signal cables.
• If electric noise comes into the product along the power line, install a noise filter at
the panel. For information on the required capacity and other specifications of a
noise filter, see related manual.
A properly selected noise filter can reduce conducted electric noise significantly.
• Provide the last Drive Units module with a terminating connector.
Otherwise malfunction could result.
• Ensure that the voltage of the AC power supply to a Converter is equal to the
rated voltage of that Converter.
Otherwise injury or a fire could result.
• Do not subject the Drive Unit to a high-voltage withstanding test.
Otherwise their semiconductor components would be damaged.
• Wiring to the Drive Unit must be done according to the relevant wiring drawing.
Otherwise damage could result.
• The screws of a terminal block must be tightened to a specified torque.
Otherwise a fire could result.
CAUTION
xiii
Safety precautions