Toshiba VF-nC1 - Manual (Page 62)

E6581090
E-10
5
Note: The motor overload protection start level is fixed at 30Hz.
VJT× 0.55
VJT× 1.0
Output frequency (Hz)
Output current reduction factor [%]
0
30Hz
[Using a VF motor (motor for use with inverter)]
■ Setting selection QNO of electronic thermal protection characteristics
Setting
value
Overload
protection
Overload stall
 ○ Ч
 ○ ○
 Ч Ч
 Ч ○
○ : valid, × : invalid
A VF motor (motor for use with an inverter) can be used in lower frequency ranges than the general-
purpose motor, but if that frequency is extremely low, the effects of cooling on the motor will deteriorate.
■ Setting the motor electronic thermal protection level 1 VJT
If the capacity of the motor being used 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 VJT so that it fits the motor's rated current.
* If the indications are in percentages (%), then 100% equals the inverter's rated output current (A).
VJT × 1.0
Output frequency (Hz)
Output current
reduction factor [%]/[A]
0
Setting of motor overload
protection start level
6Hz
VJT × 0.6
2) Inverter over load characteristics
Set to protect the inverter unit. Cannot be changed or turned off by parameter setting.
If the inverter overload trip function (QN) is activated frequently, this can be improved by
adjusting the stall operation level H downward or increasing the acceleration time CEE or
deceleration time FGE.
110% 150%
Output current [%]
Time [s]
60
Inverter overload
0
100%: inverter rated output current
* To protect the inverter, overload trip may activate in a short period of time when output current
reaches 150% or higher.
Inverter overload protection characteristics