YASKAWA VS?616G5 Owner's Manual page 23

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(f) Installation of Thermal Overload Relay
An electronic overload protective function is incorporated into the inverter. However,
connect a thermal overload relay when driving several motors with one inverter or when
using a multi−pole motor. When using a thermal overload relay, set inverter constant L1−01
to 0 (motor protection selection: disabled). Additionally, for thermal overload relay, at 50
Hz set the same rated current value as that described on the motor nameplate, or at 60 Hz
1.1 times larger than the rated current value described on the motor nameplate.
(g) Wiring Distance between Inverter and Motor
If the total wiring distance between inverter and motor is excessively long and the inverter
carrier frequency (main transistor switching frequency) is high, harmonic leakage current
from the cable will adversely to affect the inverter and peripheral devices.
If the wiring distance between inverter and motor is long, reduce the inverter carrier
frequency as described below. Carrier frequency can be set by constant C6−01.
Table 4 Wiring Distance between Inverter and Motor
Wiring Distance between
Inverter and Motor
Carrier Frequency
(Set value of constant C6−01)
(3) Grounding
S Never ground the inverter in common with welding machines, motors, or other
large−current electrical equipment. Run all the ground wires in a conduit separate
from wires for large−current electrical equipment.
S Use the ground wires described in Table 6 and keep the length as short as possible.
S When using several inverter units side by side, ground the units as shown in Fig. 10,
(a). Do not loop the ground wires as shown in (b).
(a) Acceptable
Fig. 10 Grounding of Three Inverter Units
Up to 20m
10 kHz or less
(10.0)
(b) Not Acceptable
More than 20m
5 kHz or less
(5.0)