YASKAWA CIPR-GA50C series Technical Manual page 76

3.3 Main Circuit Wiring
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Cable Length Between Drive and Motor
When the wiring between the drive and the motor is too long, voltage drop along the motor cable can decrease
motor torque, usually at low frequency output. If you connect motors in parallel with long motor cable, this is also
a problem. Drive output current increases when the leakage current from the cable increases. An increase in
leakage current can cause overcurrent and decrease the precision of the current detection.
Use the values in Table 3.4
motor wiring, if you use metal conduits or isolated cables for each phase, it will increase stray capacitance.
Table 3.4 Carrier Frequency against Cable Length Between Drive and Motor
Wiring Distance Between the Drive
and Motor
Carrier Frequency
Note:
• To set the carrier frequency in a drive that is operating more than one motor, calculate the cable length as the total distance of wiring to
all connected motors.
• If the length of the wire between the drive and an induction motor is longer than 100 m (328 ft), set A1-02 = 0[V/f].
• The maximum cable length between the drive and a PM motor is 100 m (328 ft).
• If the cable length between the drive and the motor is too long when A1-02 = 6 [AOLV/PM] or 8 [EZOLV], change the setting to A1-02
= 5 [OLV/PM].
• When you connect to a PM motor, it can be necessary to adjust the overcurrent detection. Refer to
on page 706 for more information.
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Ground Wiring
Follow the precautions to wire the ground for one drive or a series of drives.
WARNING! Electrical Shock Hazard. Make sure that the protective ground wire conforms to technical standards and local
safety regulations. The IEC/EN 61800-5-1:2007 standard specifies that you must wire the power supply to automatically de-
energize when the protective ground wire disconnects. If you turn on the internal EMC filter, the leakage current of the drive will
be more than 3.5 mA. You can also connect a protective ground wire that has a minimum cross-sectional area of 10 mm
(copper wire). If you do not obey the standards and regulations, it can cause serious injury or death.
WARNING! Electrical Shock Hazard. Ground the neutral point on the power supply of drive models 2xxxE, BxxxE, and 4xxxE to
comply with the EMC Directive before you turn on the EMC filter or if there is high resistance grounding. If the EMC filter is
switched ON without the neutral point being grounded or if there is high resistance grounding, it can cause death or serious
injury.
WARNING! Electrical Shock Hazard. Use a ground wire that complies with technical standards on electrical equipment and use
the minimum length of ground wire. Incorrect equipment grounding can cause serious injury or death from dangerous electrical
potentials on the equipment chassis.
WARNING! Electrical Shock Hazard.
Correctly ground the ground terminals. Obey federal and local electrical wiring codes for correct grounding methods. The
maximum grounding resistance is
• 200 V class: ground to 100 Ω or less
• 400 V class: ground to 10 Ω or less
If you touch electrical equipment that is not grounded, it can cause serious injury or death.
Note:
• Only use the drive grounding wire to ground the drive. Do not share the ground wire with other devices such as welding machines or
large-current electrical equipment. Incorrect equipment grounding can cause drive or equipment malfunction from electrical
interference.
• To connect more than one drive to the same grounding circuit, follow the instructions in the instruction manual. Incorrect equipment
grounding can cause drive or equipment malfunction from electrical interference.
When you connect more than one drive refer to
76
to adjust the drive carrier frequency. For systems that have 100 m (328 ft) or longer
50 m (164 ft) Maximum
15 kHz or less
Figure
Figure 3.24 Wiring More than One Drive
100 m (328 ft) Maximum
5 kHz or less
3.24. Do not loop the grounding wire.
YASKAWA SIEPC71061753A GA500 Technical Manual
More than 100 m (328 ft)
2 kHz or less
L8-27: Overcurrent Detection Gain
2