58 Guidelines for planning the electrical installation
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Separate control cable ducts
Put 24 V DC and 230 V AC (120 V AC) control cables in separate ducts, unless the
24 V DC cable is insulated for 230 V AC (120 V AC) or insulated with an insulation
sleeving for 230 V AC (120 V AC).
Implementing short-circuit and thermal overload protection
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Protecting the drive and input power cable in short-circuits
Use the fuses specified for the drive in the technical data. Make sure that also the electric
power supply network meets the specification (minimum allowed short-circuit current
that the fuse selection is based on).
The fuses restrict drive damage and prevent damage to adjoining equipment in case of
a short-circuit inside the drive. When located at the distribution board, the fuses also
protect the input power cable against short circuits.
See the drive technical data for alternative short-circuit protections.
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Protecting the motor and motor cable in short-circuits
The drive protects the motor cable and motor in a short-circuit situation when the motor
cable is sized according to the nominal output current of the drive.
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Protecting the drive, and the input power and motor cables against
thermal overload
If the cables have the correct size for the nominal current, the drive protects itself and
the input and motor cables against thermal overload. No additional thermal protection
devices are needed.
WARNING!
If the drive is connected to multiple motors, use a separate motor thermal overload
device for protecting each motor cable and motor against overload. The drive
overload protection is for the sum of the total motor load. It may not trip due to an
overload in one motor.
230 V AC
(120 V AC)
230 V AC
24 V DC
(120 V AC)
24 V DC