Mitsubishi Electric fr-e700 series, Instruction Manual

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Electromagnetic compatibility (EMC) Wiring
3 - 50
Note on selecting a suitable power supply ELCB
If your application requires by installation standards an RCD (residual current device) as up stream
protection please select according to DIN VDE 0100-530 as following:
Single phase inverter type A or B
Three phase inverter only type B
Additionally, when selecting a residual current device (RCD), leakage current caused by the mains fil-
ter, the length of the shielded motor cable and the carrier frequency must be taken into consideration.
When connecting AC current using switches without a step function, brief asymmetrical loads may re-
sult in unwanted triggering of the residual current device (RCD). It is recommendable here to use a
Type B residual current device (RCD) with delayed actuation or to switch on all three phases simulta-
neously using a main contactor.
Calculate the trip current sensitivity of the ELB as follows:
●
Breaker designed for harmonic and surge suppression:
I n
10 (Ig1 + Ign + Igi + lg2 + lgm)
●
Standard breaker:
I n
10 [Ig1 + Ign + Igi + 3 (Ig2 + lgm)]
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
I002037E
Fig. 3-44: Leakage currents
NOTE For star connection, the amount of leakage current is 1/3.
Example of leakage current per 1km
during the commercial power supply
operation when the CV cable is routed
in metal conduit
(200 V/60 Hz)
Leakage current example of 3-phase
induction motor during the
commercial power supply operation
(200 V/60 Hz)
Power supply size [mm²] Motor capacity [kW]
Leak
age curr
en
t [mA
]
Leak
age curr
ent [mA
]
Example of leakage current per 1km
during the commercial power supply
operation when the CV cable is routed
in metal conduit
(Three-phase three-wire delta
connection 400 V/60 Hz)
Leakage current example of 3-phase
induction motor during the
commercial power supply operation
(Totally-enclosed fan-cooled type
motor 400 V/60 Hz)
Leak
age curr
ent [mA
]
Leak
age curr
ent [mA
]
Power supply size [mm²] Motor capacity [kW]