Installation Of An Overload Relay - Toshiba TOSVERT VF-S11 Instruction Manual

Magnetic contactor in the secondary circuit
A magnetic contactor may be installed on the secondary side to switch controlled motors or supply com-
mercial power to the load when the inverter is out of operation.
Notes on wiring
• Be sure to interlock the magnetic contactor on the secondary side with the power supply to prevent commercial
power from being applied to the inverter output terminals.
• When installing a magnetic contactor (MC) between the inverter and the motor, avoid turning the magnetic
contactor on or off during operation. Turning the magnetic contactor on or off during operation causes a current
to rush into the inverter which could lead to malfunction.

10.3 Installation of an overload relay

1) The VF-S11 inverter has an electronic-thermal overload protective function.
In the following cases, however, an overload relay suitable for the adjustment of the motor electronic ther-
mal protection level (
the motor.
• When using a motor with a current rating different to that of the corresponding Toshiba general-purpose
• When operating a single motor with an output smaller than that of the applicable standard motor or more
2) When using the VF-S11 inverter to operate a constant-torque motor, such as the Toshiba VF motor, adjust
the protection characteristic of the electronic thermal protection unit (
3) It is recommended to use a motor with a thermal relay embedded in the motor coil to give sufficient protec-
tion to the motor, especially when it runs in a low-speed range.
10
) and appropriate to the motor used should be installed between the inverter and
motor
than one motor simultaneously.
J-4
E6581158
) to the VF motor use.