Chapter 4 Installation and commissioning
27
Ch
ap
ter 4
※
The U,V,W output end of inverter can not install phase advancing capacitor or RC absorbing
device. The inverter input power must be cut off when replacing the motor
※
Do not let metal chips or wire ends drop into inside the inverter when wiring, otherwise this
may cause malfunction to the inverter.
※
Disconnect motor or switch power-frequency power supply only when the inverter stops
output
※
In order to minimize the effects of electromagnetic interference, it is recommended that a
surge absorption device shall be installed additionally when electromagnetic contactor and
relay is closer from the inverter.
※
External control lines of inverter shall adopt isolation device or shielded wire.
※
In addition to shielding, the wiring of input command signal should also be aligned
separately, it is best to stay away from the main circuit wiring.
※
If the carrier frequency is less than 3KHz, the maximum distance between the inverter and
the motor should be within 50 meters; if the carrier frequency is greater than 4KHz, the
distance should be reduced appropriately, it is best to lay the wiring inside metal tube.
※
When the inverter is additionally equipped with peripherals (filter, reactor, etc.), firstly
measure its insulation resistance to ground by using 1000 volt megger, so as to ensure the
measured value is no less than 4 megohms.
※
When the inverter need to be started frequently, do not directly turn power off, only the
control terminal or keyboard or RS485 operation command can be used to control the
start/stop operation, in order to avoid damage to the rectifier bridge.
※
To prevent the occurrence of an accident, the ground terminal (
) must be earthed firmly
(grounding impedance should be less than 10 ohms), otherwise the leakage current will
occur.
※
The specifications on wires used by the main circuit wiring shall comply with the relevant
provisions of the National Electrical Code.
※
The motor's capacity should be equal to or less than the inverter's capacity.
4-7.
Spare Circuit
When the inverter occurs the fault or trip, which will cause a larger loss of downtime or other
unexpected faults. In order to avoid this case from happening, please additionally install spare circuit
to ensure safety.
Note: Electrical diagram MCC1 and MCC2 interlock ac contactor; Spare circuit must be
confirmed in advance and test running characteristics, make sure that the power frequency and
frequency conversion phase sequence
ST500
inverter
M
3~
R
S
T
U
V
W
K1
K2
K3
MCC1
MCC2
MCC1 & MCC2 interlocking AC contactor
R
S
T
Figure 4-19: Spare Circuit electrical diagram
