INVT Goodrive300-01A Series User Manual

Goodrive300-01A series VFD for air compressor Appendix E
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 For multi-machine connection, both ends should be connected to 120Ω terminal resistors.
Solution:
 Check and confirm the motor ground line is connected to PE terminal of the VFD (if motor
ground line has been connected to the grounding bar of VFD cabinet, measure with multimeter
to confirm that the resistance between grounding bar and PE terminal is less than 1.5Ω);
 The VFD and motor cannot be common grounded along with the communication upper PC
(PLC, HMI, touch screen, etc). It is recommended to connect the VFD and motor to the power
GND, and connect the communication upper PC to the ground pile separately;
 Try to short connect reference GND terminal of VFD signal to the reference GND terminal of
upper PC controller signal to ensure the ground potential of their communication chips is the
same;
 Try to short connect reference GND terminal of VFD signal to the grounding terminal (PE) of the
VFD.
E.3 Unstoppable or shimmering indicator caused by coupling of motor cable
Interference phenomena:
 Unable to stop
For VFD system whose start/stop is controlled by S terminal, the motor cable and control cable are
routed in the same cable tray. After system starts, it cannot stop by S terminal.
 Shimmering indicator
After VFD starts to run, shimmering, flickering or abnormal noise occurred to below equipment:
a) Relay indicator
b) Indicator of distribution box
c) PLC indicator
d) Indicating buzzer
Solution:
 Check and confirm the abnormal signal cable is routed with motor cable motor cable at a
distance of at least 20cm;
 Connect in parallel the digital input terminal (S) used for start/stop control with other idle digital
input terminals. For instance, S1 terminal is used for start/stop control, S4 terminal is idled, then
try to short connect S1 terminal with S4 terminal.
E.4 Leakage current and residual current device (RCD)
As the VFD outputs high frequency PWM voltage to drive the motor, the distributed capacitance
against the radiator from internal IGBT and between rotor and stator of the motor may cause the VFD
to generate high frequency leakage current against the ground. While the RCD is used to detect the
power frequency leakage current when grounding fault occurred to electrical circuit, the application of
VFD may cause mal-operation of RCD.
How to select RCD:
Due to the specialty of VFD system, it is required that the rated residual operating current should be
above 200mA for regular RCDs at all levels, and the VFD must be grounded with proper technics.
As for the setting time of RCD, the time limit of preceding action should be longer than the secondary

INVT Goodrive300-01A Series Specifications

General

Brand	INVT
Model	Goodrive300-01A Series
Category	DC Drives
Language	English