Hitachi L100 IP Series, Инструкция по эксплуатации

Страница: 12 / 94

Chapter 1 – Safety precautions
1-4
installed well apart from the inverter. It is also effective to shield the whole inverter
structure (refer to figure below, left part).
Motor
Inverter
L1(L1)
L2
L3(N)
T1(U)
T2(V)
T3(W)
R2
S2
T2
Pow
er
supply
R1
S1
T1
EMI filter +
Grounding
Inver
te
r
EM
I
filte
r
Motor
Pow
er
supply
Noise
Noise
Grounded
frame
Completely ground the frame
with as short a wire as possible.
Grounded piping
or shielded wire
Added EMI filter on the input side of the inverter also reduces the effect of noise from
commercial power lines on external devices (refer to figure above).
CAUTION EFFECTS OF DISTRIBUTER LINES ON INVERTERS
In the cases mentioned below involving a general purpose inverter, a large peak
current flows on the power supply side, sometimes destroying the converter module:
A) The unbalance factor of the power supply is 3% or higher.
B) The power supply capacity is set at least ten times greater than the inverter
capacity (i.e. 500kVA or more)
C) When abrupt power supply changes are to be expected. Some examples:
1)
Several inverters are interconnected using a short bus to the same power
supply.
2) A thyristor converter and an inverter are interconnected using a short bus.
3) An installed power factor compensating device is connected or disconnected.
In the cases mentioned above we recommend installing an AC reactor of 3% voltage
drop at rated current with respect to the supply voltage on the power supply side.
CAUTION When an EEPROM error occurs (trip E 08 ) all parameter values have to be checked
for correctness (especially the RS input).
CAUTION When the intelligent digital inputs FW or RV are configured as normally closed
contact (standard setting is normally open), then the inverter starts automatically. Do
not configure these inputs as normally closed inputs unless absolutely necessary.
CAUTION Factory setting of the carrier frequency is different for diferent types of the inverter.
This setting is at the same time also highest allowable carrier frequency without
derating output power. See bottom of the terminal cover for reference.
GENERAL NOTICE
In all the illustrations and figures in this manual, covers and safety devices are
occasionally omitted in order to better describe the details. When the inverter is
operated make shure that all the covers and safety devices are placed in their correct
positions.