Mitsubishi Electric FR-A700 Technical Manual page 251

Torque limit
+
Reverse
regeneration
Terminal 1 input or
internal torque limit
([Pr.22] etc.) whichever
is smaller
quad4
Reverse rotation
Speed
quad3
Terminal 4 input or
internal torque limit
([Pr.22] etc.) whichever
is smaller
Reverse
driving
-
Rated speed
Torque limit by analog input can be calibrated using
calibration parameter [C16 to C19 (Pr. 919, Pr. 920)],
[C38 to C41 (Pr. 932, Pr. 933)], [C34 to C37 (Pr. 928,
929)]. (Refer to page 320)
(5) Second torque limit level (TL signal) [Pr. 815]
For [Pr. 815 Torque limit level 2], the [Pr. 815] value is a
torque limit value regardless of [Pr. 810 Torque limit
input method selection] when the torque limit selection
signal (TL) is ON.
Set [Pr. 178 to 189 Input terminal function selection] to
assign a function to the TL signal.
Torque limit
Reverse
regeneration
[Pr.815]
quad4
-
[Pr.815]
quad3
Reverse
driving
Reverse
rotation
Rated speed
(6) Torque limit value during acceleration/
deceleration [Pr. 816, 817]
You can set torque limit during acceleration and
deceleration individually.
Torque limit by [Pr. 816 Torque limit level during
acceleration] and [Pr. 817 Torque limit level during
deceleration] is shown below.
[Pr. 816] [Pr. 22]
Torque limit level during acceleration Torque limit level
Torque limit level
Output
1s
frequency
(Hz)
Set
frequency
Acceleration
Constant speed
(7) Setting increments switchover of the
torque limit level [Pr. 811]
By setting [Pr. 811 Set resolution switchover = 10, 11]
under vector control, the setting increments of [Pr. 22
Torque limit level] and [Pr. 812 to Pr. 817 Torque limit
level] can be switched to 0.01%.
Forward
driving
Terminal 4 input or
internal torque limit
([Pr.22] etc.) whichever
is smaller
quad1
Forward rotation
quad2
Terminal 1 input or
internal torque limit
([Pr.22] etc.) whichever
is smaller
Forward
regeneration
Forward
driving
[Pr.815]
quad1
+
Speed
[Pr.815]
quad2
Forward
regeneration
Forward
rotation
[Pr. 817]
Torque limit level during deceleration
After the state where
difference between the
set speed and running
speed is within ±2Hz has
persisted for 1s, torque
limit level during
acceleration / deceleration
[Pr. 816] or [Pr. 817] shifts to
torque limit level during
constant speed [Pr. 22].
Time
Deceleration
Note that the internal resolution of the torque limit is
12
0.024% (100/2
resolution is rounded off.
The fraction less than the resolution equivalent to
0.1% is rounded off even if [Pr. 811 = 10, 11] when
Real sensorless vector control is selected.
When the torque restriction setting increments have
been changed (0.1%
because the settings of [Pr. 22, Pr. 812 to Pr. 817] are
multiplied by 1/10 (ten times). For example, when [Pr.
22 = 150.00%] and [Pr. 811 = 10 (0.01%)
[Pr. 22 = 1500.0%] and the maximum torque is 400%.
(Refer to page 343 for switchover of speed setting
increments.)
(8) Torque characteristic in the constant
power range [Pr. 803].
You can select whether the torque limit in the
constant power range be constant torque limit
(setting is "1") or constant power limit (initial setting is
"0") using [Pr. 803 Constant power range torque
characteristic selection] under torque limit operation.
Torque
Constant torque range
Base speed
(9) Fault stop when torque limit is activated
[Pr. 865, 874]
This function makes an inverter trip if the torque limit
is activated to stall the motor.
The motor stalls if the torque limit is activated under a
high load applied during speed control or position
control. At this time, if the motor speed is lower than
the speed set in [Pr. 865 Low speed detection] and also
the output torque exceeds the level set in [Pr. 874 OLT
level setting] for 3s, it is regarded as a stop effected by
stall prevention and E. OLT is output, resulting in a
fault.
Torque
Output torque
Output
frequency
[Pr.865]
Start
signal
(STF)
Fault
output
285
PARAMETER
) and the fraction less than the
0.01%), reset is necessary
1 (0.1%)],
Constant power range
[Pr.803 = 1]:
constant torque limit
[Pr.803 = 0]:
constant power limit
(torque reduction)
Speed
Torque limit
[Pr.874]
3s
E.OLT occurrence
2
Time
Time