Hitachi SJ700D-004L Instruction Manual Download Page 38

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Chapter 2

Installation and Wiring

2-17

(3) Applicable peripheral equipment

See Item (4), "Recommended cable gauges, wiring accessories, and crimp terminals."

Note 1: The peripheral equipment described here is applicable when the inverter connects a

standard Hitachi 3-phase, 4-pole squirrel-cage motor.

Note 2:    Select breakers that have proper capacity. (Use breakers that comply with inverters.)
Note 3:    Use earth-leakage breakers (ELB) to ensure safety.
Note 4:    Use copper electric wire (HIV cable) of which the maximum allowable temperature of the

insulation is 75°C.

Note 5: If the power line exceeds 20 m, cable that is thicker than the specified applicable cable

must be used for the power line.

Note 6: Use a 0.75 mm

cable to connect the alarm output contact.

Note 7: Tighten each terminal screw with the specified tightening torque. Loose terminal screws

may cause short circuits and fire. Tightening a terminal screw with excessive torque may
cause damage to the terminal block or inverter body.

Note 8: Select an earth-leakage breaker (ELCB) of which the rated sensitivity current matches the

total length of cables connected between the inverter and power supply and between the
inverter and motor. Do not use a high-speed type ELB but use a delayed-type ELB because
the high-speed type may malfunction.

Note 9: When a CV cable is used for wiring through a metal conduit, the average current leakage

is 30 mA/km.

Note 10: When an IV cable, which has a high relative dielectric constant, is used, the leakage

current is about eight times as high as the standard cable. Therefore, when using an IV
cable, use the ELB of which the rated sensitivity current is eight times as high as that given
in the table below. If the total cable length exceeds 100 m, use a CV cable.

Total cable length

Sensitivity current (mA)

100 m or less

300 m or less

100

Name

Description

Reactor on input side (for harmonic
control, power supply coordination,
and power factor improvement)
(ALI-XXX)

Use this reactor to control harmonic waves or when the imbalance of power
supply voltage is 3% or more, when the power supply capacity is 500 kVA or
more, or when the power voltage may change rapidly. This reactor also
improves the power factor.

Noise filter for inverter
(NF-XXX)

This noise filter reduces the conductive noise that is generated by the
inverter and transmitted in cables. Connect this noise filter to the primary
side (input side) of the inverter.

Radio noise filter
(Zero-phase reactor) (ZCL-X)

The inverter may generate radio noise through power supply wiring during
operation. Use this noise filter to reduce the radio noise (radiant noise).

Radio noise filter on input side
(Capacitor filter) (CFI-X)

Use this noise filter to reduce the radiant noise radiated from input cables.

DC reactor (DCL-X-XX)

Use this reactor to control the harmonic waves generated by the inverter.

Braking resistor
Regenerative braking unit

Use these devices to increase the braking torque of the inverter for operation
in which the inverter turns the connected load on and off very frequently or
decelerates the load running with a high moment of inertia.

Noise filter on the output side
(ACF-CX)

Connect this noise filter between the inverter and motor to reduce the
radiant noise radiated from cables for the purpose of reducing the
electromagnetic interference with radio and television reception and
preventing malfunctions of measuring equipment and sensors.

Radio noise filter
(Zero-phase reactor)
(ZCL-XXX)

Use this noise filter to reduce the noise generated on the output side of the
inverter. (This noise filter can be used on both the input and output sides.)

AC reactor for the output side
For reducing vibrations and
preventing thermal relay malfunction
(ACL-X-XX)

Using the inverter to drive a general-purpose motor may cause larger
vibrations of the motor when compared with driving it directly with the
commercial power supply. Connect this AC reactor between the inverter and
motor to lessen the pulsation of motor. Also, connect this AC reactor
between the inverter and motor, when the cable length between them is
long (10 m or more), to prevent thermal relay malfunction due to the
harmonic waves that are generated by the switching operation on the
inverter. Note that the thermal relay can be replaced with a current sensor to
avoid the malfunction.

LCR filter

Connect this noise filter between the inverter and motor to convert the
inverter output into a sinusoidal waveform and to reduce the motor
vibration, motor noise and the radiant noise radiated from cables.