Toshiba Tosvert VF-AS1 - Manual (Page 78)

E6581301
E-12
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2) Decreasing output voltage
Setting of V/f control mode selection RV= (Voltage decrease curve
This is appropriate for load characteristics of such things as fans, pumps and blowers in which the torque in relation
to load rotation speed is proportional to its square.
Base frequency voltage 1
XNX
O
u
tput
v
o
ltage
[V]
XD
Base frequency XN
0 Output frequency [Hz]
3) Increasing starting torque
Setting of V/f control mode selection RV= (Automatic torque boost)
Detects load current in all speed ranges and automatically adjusts voltage output (torque boost) from inverter.
This gives steady torque for stable runs.
Base frequency voltage 1
XNX
O
u
tp
ut v
o
ltage
[V]
Output frequency [Hz]
Base frequency XN
0
: The torque
boost rate is
adjusted
automatically.
Note:This control system can oscillate and destabilize runs depending on the load. If that should happen, set V/f
control mode selection RV to (Constant torque characteristics) and increase torque manually.
+ Motor constant must be set.
If the motor you are using is a 4P Toshiba standard motor and if it has the same capacity as the inverter, there is
basically no need to set the motor constant.
To set the motor constant, enter the following information that is indicated on the motor nameplate, and then
execute the auto-tuning 1 command (H=).
XN
(Base frequency), XNX (Base frequency voltage), H (Motor rated capacity), H (Motor rated
current), H(Motor rated rotational speed)