Hitachi SJ300 Series Power Supply User Manual


 
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CAUTION: Do not insert leading power factor capacitors or surge absorbers between the
output terminals of the inverter and motor.
CAUTION: Be sure to connect the grounding terminal to earth ground.
CAUTION: When inspecting the unit, be sure to wait five minutes after tuning OFF the power
supply before opening the cover.
CAUTION: SUPPRESSION FOR NOISE INTERFERENCE FROM INVERTER
The inverter uses many semiconductor switching elements such as transistors and IGBTs.
Thus, a radio receiver or measuring instrument located near the inverter is susceptible to noise
interference.
To protect the instruments from erroneous operation due to noise interference, they should be
used well away from the inverter. It is also effective to shield the whole inverter structure.
The addition of an EMI filter on the input side of the inverter also reduces the effect of noise
from the commercial power line on external devices.
Note that the external dispersion of noise from the power line can be minimized by connecting
an EMI filter on the primary side of inverter.
Power
Input
Inverter
R, S, T
Ground fault
interrupter
U, V, W
Motor
GND lug
Surge absorber
Leading power
factor capacitor
GFI
L1, L2, L3
Power
source
R1
EMI filter
S1
T1
R2
S2
T2
R
S
T
U
V
W
Motor
Inverter
Inverter
Remote
operator
EMI filter
noise
Motor
Conduit or shielded cable—
to be grounded
Grounded frame
Completely ground the enclosed
panel, metal screen, etc. with as
short a wire as possible.
L1
L2
L3
T1
T2
T3