Toshiba Tosvert VF-S15 Instruction Manual page 369

[Using a VF motor (motor for use with inverter)]
 Setting of electronic thermal protection characteristics selection olm
Setting value




VF motors (motors designed for use with inverters) can be used in frequency ranges lower than those for
standard motors, but their cooling efficiency decreases at frequencies below 6Hz.
 Setting of motor electronic thermal protection level 1 thr (Same as f173)
If the capacity of the motor is smaller than the capacity of the inverter, or the rated current of the motor is
smaller than the rated current of the inverter, adjust the electronic thermal protection level 1  so that it fits
the motor's rated current.
Output current reduction factor
2) Motor 150%-overload detection time f607
Parameter f607 is used to set the time elapsed before the motor trips under a load of 150% (overload trip 2)
within a range of 10 to 2400 seconds.
3) Inverter overload detection method f631
As this function is set to protect the inverter unit, this function cannot be turned off by parameter setting.
The inverter overload detection method can be selected using parameter f631 (Inverter overload detection method).
If the inverter overload trip function (ol1) is activated frequently, this can be improved by adjusting the stall operation
level f601 downward or increasing the acceleration time acc or deceleration time dec.
 = (150%-60s)
Protection is given uniformly regardless of temperature by the 150%-60 sec overload curve.
 = (Temperature estimation)
This parameter adjusts automatically overload protection, predicting the inverter internal temperature rise.
4) Electronic thermal memory f632
When the power is OFF, it is possible to reset or maintain the overload totaling level.
This parameter's settings are applied both to the motor's electronic thermal memory and the electronic thermal memory
for inverter protection.
5) Overload alarm level f657
When the motor overload level reaches to f657 setting value (%) of overload trip (ol2) level, "l" will be displayed
on the left side digit and the "l" and output frequency monitor will be blinking alternately on overload alarm status.
Overload alarm signal can be output from output terminal.
Overload protection Overload stall
valid invalid
valid valid
invalid invalid
invalid valid
[%]/[A]
×1.0
×0.6
0
6Hz
Note) The start level for motor overload reduction is fixed at 6 Hz.
Q-13
Output frequency (Hz)
E6581926