Mitsumi electronic FR-F520-0.75K, 55K instruction manual Example

INSTALLATION AND WIRING

(2) Selection the rated sensitivity current for the earth leakage circuit breaker

When using the earth leakage circuit breaker with the inverter circuit, select its rated sensitivity current as follows, independent of the carrier frequency setting:

• Progressive Super Series (Type SP, CF, SF,

CP)

Example of leakage current per 1km

Leakage current example

Rated sensitivity current:

for commercial power supply operation

of 3-phase induction motor

when CV cable is routed in metal conduit

during commercial power

l∆

n ≥

10 ⋅

(lg1 + lgn + lg2 + lgm)

(200V 60Hz)

supply operation

• Conventional NV series (Type CA, CS, SS

(200V 60Hz)

produced prior to '91)

120

2.0

Rated sensitivity current:

(mA)

(mA)

100

l∆

n ≥

10 ⋅

{lg1 + lgn + 3 ⋅ (lg2+lgm)}

1.0

lg1, lg2: leakage currents of cable path

current

80

current

0.7

60

0.5

during commercial power supply

Leakage

Leakage

0.3

operation

40

0.2

20

lgn*

: leakage current of noise filter on

inverter input side

0

0.1

2 3.5

8 14 22 38 80 150

1.5

3.7 7.5 1522 37 55

lgm

: leakage current of motor during

5.5

30 60 100

2.2

5.5 1118.53045

commercial power supply operation

Cable size (mm2 )

Motor capacity (kW)

<Example>

5.5mm2

5m (16.40feet)

5.5mm2 70m (16.40feet)

2

NV

Noise

filter

Inverter

IM 3

200V 2.2kW (3HP)

Ig1

Ign

Ig2

Igm

Note

1. The NV should be installed to the

Progressive Super

Conventional NV

primary (power supply) side of the

Series

(Type CA, CS, SS)

(Type SP, CF, SF, CP)

inverter.

Leakage current Ig1 (mA)

33 ⋅

5m (16.40feet)

= 0.17

2. Ground fault in the secondary side of the

1000m (3280.80feet)

Leakage current Ign (mA)

0 (without noise filter)

inverter can be detected at the running

frequency of 120Hz or lower.

Leakage current Ig2 (mA)

33 ⋅

70m (229.66feet)

= 2.31

1000m (3280.80feet)

3.

If the

connection neutral point ground

Motor leakage current Igm (mA)

0.18

fault in the inverter secondary side.

Total leakage current (mA)

2.66

7.64

The protective ground resistance of the

Reted sensitivity current (mA)

30

100

load equipment should be 10Ω or less.

( ≥

Ig ⋅ 10)

4. When the breaker is installed on the secondary side of the inverter, it may be unnecessarily operated by harmonics if the effective value is less than the rating. In this case, do not install it since the eddy current and hysteresis loss increase and the temperature rises.

*Be careful of the leakage current value of the noise filter installed on the inverter input side.

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