Mitsubishi Electric FR-V560 Instruction Manual page 29

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(3) Selection of rated sensitivity current of ground leakage breaker
When using the ground leakage breaker with the inverter circuit, select its rated sensitivity current as follows,
independently of the PWM carrier frequency.
• Breaker for harmonic and surge
Rated sensitivity current
I∆n ≥10
×
(Ig1 + lgn + Ig2 + Igm)
• Standard breaker
Rated sensitivity current
I∆n ≥10
×
{Ig1 + Ign + 3
Ig1, Ig2: Leakage currents of cable path
during commercial power supply operation
Ign *:Leakage current of noise filter on
inverter input side
Igm:Leakage current
commercial power supply operation
<Example>
CAUTION
• Install the NV on the primary (power supply) side of the inverter.
• In the connection neutral point grounding system, the sensitivity current is purified against an
ground fault in the inverter secondary side. Grounding must conform to the requirements of national
and local safety regulations and electrical codes. (JIS, NEC section 250, IEC 536 class 1 and other
applicable standards)
• 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 the breaker since the eddy current and hysteresis loss will increase, leading
to temperature rise.
* Note the leakage current value of the noise filter installed on the inverter input side.
Leakage current Ig1 (mA)
Leakage current Ign (mA)
Leakage current Ig2 (mA)
Motor leakage current Igm
(mA)
Total leakage current (mA)
Rated sensitivity current
( ≥Ig
×
10)
(mA)
×
(Ig2 + Igm)}
of motor during
2mm 5m (16.40feet)
2
Noise
NV
filter
Ig1 Ign
Breaker for Harmonic and Surge
Leakage Current Example of Cable
Path per 1km during Commercial
Power Supply Operation When CV
Cable Is Routed in Metal Conduit
(200V 60Hz)
120
100
80
60
40
20
0
2 3.5 8 14 22 38 80 150
5.5 30 60 100
2
Cable size (mm )
2mm 70m (229.65feet)
2
3φ
IM
Inverter 200V1.5kW
Ig2 Igm
5m(16.40feet)
20 ×
1000m(3280feet)
0 (without noise filter)
70m(229.65feet)
20 ×
1000m(3280feet)
0.16
1.66
30
20
Leakage Current Example of
3-Phase Induction Motor during
Commercial Power Supply Operation
(200V 60Hz)
2.0
1.0
0.7
0.5
0.3
0.2
0.1
1.5 3.7 7.5 15 22 37 55
2.2 5.5 11 18.5 30 45
Motor capacity (kW)
Standard Breaker
= 0.10
= 1.40
4.78
100