Installation Of A Molded-Case Circuit Breaker (Mccb) And Earth Leakage Circuit Breaker (Elcb); Installation Of A Magnetic Contactor (Mc); Installation On The Primary Side - Toshiba TOSVERT VF-AS3 Instruction Manual

• Install a surge absorber on the exciting coil of a magnetic contactor (MC) and relays.
• When using an auxiliary contacts 2a type magnetic contactor (MC), use the 2a contacts in parallel to
increase the liability of the contacts.
• Selection is for assuming a normal power supply capacity and using a Toshiba 4-pole standard motor
with input power 200 V/400 V-50 Hz.
• For the influence of the leakage current, refer to [2. 4. 3].
10. 2. 2 Installation of a molded-case circuit breaker (MCCB)
and earth leakage circuit breaker (ELCB)
For protection of the wiring system, install a molded-case circuit breaker (MCCB) between the power
supply and the inverter (primary side).
An earth leakage current breaker (ELCB) that is equipped with a function to shut off by detecting leak-
age current can be also installed. However, be cautious that an earth leakage circuit breaker (ELCB)
may operate improperly, because the leakage current becomes large due to the influence of a wiring
method, a built-in noise filter, etc.
Because the short-circuit current is different with power supply capacity and wiring system conditions,
select molded-case circuit breaker (MCCB) or earth leakage circuit breaker (ELCB) depending on the
inverter type and input current in the table [10. 2. 1].
• When complying with UL Standard and CSA Standard, a fuse needs to be installed on the pri-
Memo
mary side of the inverter. For details, refer to [9. 2. 3].
10. 2. 3

Installation of a magnetic contactor (MC)

When installing a magnetic contactor (MC) on the primary or secondary side of the inverter, select fol-
lowing the below.

■ Installation on the primary side

When the power side and the inverter need to be detached in the following cases, install a magnetic
contactor (MC) between the power supply and the inverter (primary side).
Select a magnetic contactor (MC) depending on the inverter type and input current in the table [10.
2. 1].
• Thermal relay on the motor is activated
• Protection detection relay (FL) inside the inverter is activated
• Not to automatically restart at restoration of power after power failure
• When using the braking resistor (option), the thermal relay of the braking resistor is activated
To open the power circuit (primary side) when the protective function detection relay inside the
inverter is activated, the molded-case circuit breaker (MCCB) with a power cutoff device can be
installed instead of magnetic contactors (MC). Make sure the molded-case circuit breaker (MCCB)
trips at the contact of protection detection relay.
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10. Selection and installation of peripheral devices
E6582062
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