3.3.6 Precautions for installation
(1) The circuit breaker on the power supply side may trip according to some failures of the converter.
In such a case, the auxiliary power supply is also turned off and the failure is not retained. When the circuit
breaker is turned on to turn on the contactor, the breakage inside the converter may propagate.
To prevent this kind of trouble from propagating, it is recommended to retain the alarm signal of the converter
in an electrically reset relay.
The circuit without an electrically reset relay is shown below.
Figure 3.3-13 Precautions for installation
(2) Because a high frequency current flows through the boosting reactor, the reactor itself generates slight
electromagnetic noise.
(3) Be sure to connect to a power supply rated at larger than the power supply capacity requirement specified in
Section 10.1 "Standard Specifications."
(If the power supply capacity is too small, the converter and/or inverter may be broken due to distortion of
waveform of the power supply.)
Among all, problems may arise if the power supply boosted with a small capacity transformer is used for the
main circuit power supply for the sequence check of the control panel. In this case, disconnect the circuit across
RUN and CM of the converter and perform the sequence check of other parts without operating the converter.
52
RUN
30A
30C
Opera-
tion
FX
Operation
preparation
S
30X
R
30
Reset
30X
RUN
CM
THR
CM
FWD
CM
30A
30B
30C
Y5A
Y5C
30C
30C
30A
30B
30C
PWM converter
Inverter
30A
30A
52
30
RUN
FX
30X
RUN
CM
THR
CM
FWD
CM
30A
30B
30C
Y5A
Y5C
30B
30C
30A
30B
30C
PWM converter
Inverter
52
RUN
30B
30C
Operation
FX
Operation
preparation
RUN
FX
52
3-21
