# Load Torque High Speed Frequency Control (pr. 4, Pr. 5, Pr. 270 To Pr. 274) - Mitsubishi Electric FR-A740-00023 Instruction Manual

Fr-a700 series.

## 4.25.3 Load torque high speed frequency control (Pr. 4, Pr. 5, Pr. 270 to Pr. 274)

Load torque high speed frequency control is a function
which automatically sets the operational maximum
More specifically, the magnitude of the load is judged
according to the average current at a certain time after
starting to perform operation at higher than the preset
This
function
is
designed
automatically under light load, for example to minimize
the incoming/outgoing time in a multi-story parking lot.
Parameter
Name
Number
Multi-speed setting (high
4
speed)
Multi-speed setting (middle
5
speed)
torque high-speed
270
frequency control
selection
High-speed setting
271
maximum current
Middle-speed setting
272
minimum current
273
Current averaging range
Current averaging filter
274
time constant
* When Pr. 570 Multiple rating setting ≠ "2", performing inverter reset and all parameter clear changes the setting range. (Refer to page
149)
<Connection diagram>
Source logic
Pr. 186 = 19
* The used terminal changes according to the Pr. 180 to Pr. 189 (input terminal function selection) settings.
to
increase
speed
Initial
Setting
Value
Range
50Hz
0 to 400Hz
30Hz
0 to 400Hz
0
50%
0 to 220% *
100%
0 to 220% *
0 to 400Hz
9999
16
1 to 4000
MCCB
Power supply
Start signal
Special operation and frequency control
<Without high-speed
frequency control>
Whether there is a load or
not, the lift is moved
vertically at the same speed.
Set the higher-speed frequency.
Set the lower-speed frequency.
0
Normal operation
1
Stop-on-control (refer to page 205)
2
Load torque high speed frequency control
Stop-on-contact (refer to page 205) + load torque high
3
speed frequency control
Set the upper and lower limits of the current at high and
middle speeds.
Average current during acceleration from (Pr. 273 × 1/2)
Hz to (Pr. 273) Hz can be achieved.
Average current during acceleration from (Pr. 5 × 1/2) Hz
9999
to (Pr. 5) Hz is achieved.
Set the time constant of the primary delay filter relative to
the output current.
The time constant [ms] is 0.75
value is 12ms.
A larger setting provides higher stability but poorer response.
MC
Mechanical
brake
R/L1
U
S/L2
V
Motor
T/L3
W
STF
CS(X19)
*
PC
<With high-speed
frequency control>
Light
Faster
The lift with a light load or without
a load is moved faster than the lift
(The output frequency is increased.)
Description
×
Pr. 274 and the initial
4
361