Mitsubishi Electronics A800 ユーザーズマニュアル



When using an earth leakage circuit breaker with the inverter circuit, select its rated sensitivity current as follows, 
independently of the PWM carrier frequency.

 • Inverter/converter unit leakage current

400 V class (input power condition: 440 V/60 Hz, power supply unbalance within 3%)

 • Breaker designed for harmonic and surge suppression

Rated sensitivity current
I

n  10  (Ig1 + Ign + Igi + Ig2 + Igm)

 • Standard breaker

Rated sensitivity current
I

n  10  {Ig1 + Ign + Igi + 3  (Ig2 + Igm)}

Ig1, Ig2:  Leakage currents in wire path during commercial 

power supply operation

Ign: 

Leakage current of inverter input side noise filter

Igm: 

Leakage current of motor during commercial power 
supply operation

Igi: 

Leakage current of inverter unit
(When the converter unit is connected, add the 
leakage current of converter unit.)

<Example>

 • Selection example for the   connection of the 400 V class

Leakage current Ig1 (mA)

1

66 

5 m

= 0.11

3

1000 m

Leakage current Ign (mA)

0 (without noise filter)

Leakage current Igi (mA)

1 (without EMC filter)
For the leakage current of the inverter, refer to 
the following table.

Leakage current Ig2 (mA)

1

66 

60 m

= 1.32

3

1000 m

Motor leakage current Igm (mA)

0.36

Total leakage current (mA)

2.79

6.15

Rated sensitivity current (mA) (

 Ig  10) 30

100

35

2

2

35

2

70

2

2

1

1

2

1

2

1

(mA)

Motor capacity (kW)

For "   " connection, the amount of leakage current is appox.1/3 of the above value.

(Three-phase three-wire delta
 connection 400V60Hz)

Example of leakage current per 1km during 
the commercial power supply operation 
when the CV cable is routed in metal conduit

Leakage current example of three-
phase induction motor during the 
commercial power supply operation

(Totally-enclosed fan-cooled
 type motor 400V60Hz)

0

2 0

4 0

6 0

8 0

100

120

leakage currents (mA)

leakage currents (mA)

2 3.5

5.5

8 1422

30

38

60

80

100

150

Cable size (mm

2

)

0. 1

0. 2

0. 3

0. 5

0. 7

1. 0

2. 0

1. 5 3. 7

2. 2

7. 5 1522

11

37

30

55

45

5.5

18. 5

Noise 

filter

Inverter

ELB

Ig1

Ign

Igi

Ig2

Igm

M

5.5mm

2 

   5m

5.5mm

2    

60m

400V

2.2kW

3

φ

Phase 
earthing
(grounding)

Earthed-neutral 
system