Hitachi SJ Series User Manual page 63

Chapter 7
Input terminal for main power supply (R,S,T)
(continued)
・Do not use a power supply that is
applicable to the following conditions.
Otherwise, the internal converter module
Failure
may be burned.
1. Unbalance of power supply voltage 3% or
above.
2. The power supply capacity is 10 times or
more the appropriate capacity of ND rating
Prohibited
motor and it is not less than 500kVA.
3. If a rapid change of power supply is made
to power.
(Example 1) If more than one inverters are
installed and connected with each other by
a short bus.
(Example 2) If a phase leading capacitor is
inserted or shut off.
Inverter output terminal (U,V,W)
.
・Perform wiring only with wires whose
thickness is equivalent to or above that of
the applicable wires. Otherwise, the output
DANGER
voltage may drop between the inverter and
motor. Especially during output at low
speed, voltage drop caused by wiring
Do
reduces the torque of motor.
・Do not attach a phase leading capacitor or
surge absorber, because they may cause
Failure
inverter errors or damage the capacitor or
surge absorber.
Prohibited
・When you connect more than one motors,
install a thermal relay for each of them.
Failure
Do
!
* For compliance with CE standards and UL standards, check "1.6
Compliance with European Directive (CE)" and "1.7 Compliance
with UL Standards".
* If export to the U.S. or Canada or compliance with UL/cUL
standards is required, you need to use wires and breakers
specified in the UL/cUL standards. When connecting wires to the
main circuit terminal block, use a round crimping terminal
(UL-certified item) suitable for the wires for use. Use a crimp tool
recommended by the manufacturer of the crimping terminal to
crimp the terminal.
* The screw size may differ depending on the terminal. For the
terminal screw size of the power line, see "7.5.4 Recommended
Wire Diameter, Wiring Tools, and Crimping Terminals. For others,
see figures in "7.5.6 Wiring Locations".
Wire Connection and Optional Devices
・ Do not turn on and off the power
frequently, which should not do more than
once every 3 minutes.
Failure
Prohibited
・If the wire length exceeds 20m, due to stray
capacity or inductance of the wire, surge
voltage may be generated on the motor
Burnout
terminal (especially on 400V class), which
may burn the motor.
・We have a special filter for suppressing
surge voltage. Please contact our sales
Do
office.
・Set the RC value of the thermal relay to be
1.1 times the rated current of motor. The
thermal relay may trip earlier than intended
Failure
depending on the wire length. In such a
case, attach an AC reactor on the output
side of inverter.
Do
* For wiring to th inverter, crimping terminal, and tightening torque
of terminal screws, see tables in "7.5.4 Recommended Wire
Diameter, Wiring Tools, and Crimping Terminals.
* The recommended wire diameter and amplifier size vary
depending on the settings of load rating (ND/LD/VLD).
* The wire diameters shown in tables in "7.5.4 Recommended
Wire Diameter, Wiring Tools, and Crimping Terminals" indicate
design values for HIV wire (resistant to 75°C heat).
* When connecting wires to the main circuit terminal block, use a
round crimping terminal in accordance with the wires for use.
Use a crimp tool recommended by the manufacturer of the
crimping terminal to crimp the terminal.
* When replacing SJ700 with this device, for different wire
diameter, etc., please contact the customer communication
center described in the back cover.
7-8