xii

CAUTION: EFFECTS OF POWER DISTRIBUTION SYSTEM ON INVERTER

In the case below involving a general-purpose inverter, a large peak current can flow on the power supply side, sometimes destroying the converter module:

1.The unbalance factor of the power supply is 3% or higher.

2.the power supply capacity is at least 10 times greater than the inverter capacity (or the

power supply capacity is 500kVA or more).

3.Abrupt power supply changes are expected, due to conditions such as:

a.Several inverters are interconnected with a short bus.

b.A thyristor converter and an inverter are interconnected with a short bus.

c.An installed phase advance capacitor opens and closes.

Where these conditions exist or when the connected equipment must be highly reliable, you MUST install an input side AC-reactor of 3% (at a voltage drop at rated current) with respect to the supply voltage on the power supply side. Also, where the effects of an indirect lightening strike are possible, install a lightening conductor.

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 the inverter.

SFEF model has integrated filter complies to EN61800-3 category C1.

HFEF model has integrated filter complies to EN61800-3 category C2.

EMI Filter

EMI Filter

 

R1

R2

L1

U

 

S1

S2

L2

V

Motor

 

T1

T2

L3

W

 

noise

EMI Filter

Inverter

Motor

 

 

 

 

 

 

 

 

 

 

 

 

Completely ground the

Remote

 

 

 

 

 

 

 

 

 

 

enclosure panel, metal

Operator

 

 

 

 

 

 

 

 

 

Grounded frame

 

 

 

 

 

 

 

 

 

screen, etc. with as short

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

a wire as possible.

 

 

Conduit or shielded cable

 

 

 

-- to be grounded

 

 

 

 

 

 

 

 

 

 

 

 

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Hitachi X200 Series instruction manual Xii, Remote