Mitsubishi Electric 800 Series Instruction Manual page 468

Load torque high speed frequency control setting
• Set "2, 3 or 13" in Pr.270 Stop-on contact/load torque high-speed frequency control selection.
• When the load torque high-speed frequency selection (X19) signal ON, the inverter automatically adjusts the maximum
frequency in the range between the Pr.4 Multi-speed setting (high speed) and Pr.5 Multi-speed setting (middle speed)
in accordance with the average current in the current averaging range. The current averaging range is from the 1/2 the Pr.5
to the full Pr.5 setting (in the current averaging range).
• To use the X19 signal, set "19" in any of Pr.178 to Pr.189 (Input terminal function selection) to assign the function to an
input terminal.
• This is valid in External operation mode and Network operation mode.
• The control can be activated at every start.
Operation of load torque high-speed frequency control
• When the average current of the current averaging range (chart A below) during operation with the X19 signal ON is the
"inverter rated current  Pr.271 setting (%)" or less, the maximum frequency automatically becomes the Pr.4 Multi-speed
setting (high speed) setting value.
• When the average current of the current averaging range (chart B below) during operation with the X19 signal ON is greater
than the "inverter rated current  Pr.272 setting (%)", the maximum frequency automatically becomes the Pr.5 Multi-speed
setting (middle speed) setting value.
• During regeneration load operation, the Pr.5 setting is the maximum frequency regardless of the average current.
• When Pr.273 is used, the current averaging range can be set between one half of the frequency of the Pr.273 setting value
and the Pr.273 set frequency. (However, the setting value must be smaller than Pr.5 setting.)
Pr.4
Pr.5
1
Pr.5
2
Current averaging range Current averaging range Current averaging range
Less than Less than Less than
Pr.271 setting rated current Pr.271 setting rated current Pr.271 setting rated current
STF
ON
(STR)
ON
X19
• When the average current is larger than "inverter rated current  Pr.271 setting (%)" and smaller than "inverter rated current
 Pr.272 setting (%)", linear compensation is performed as shown below.
Power running
A
Current averaging range Current averaging range Current averaging range
Pr.272 setting rated current Pr.272 setting rated current Pr.272 setting rated current
or more or more or more
OFF
Pr.4
(60Hz/50Hz)
Pr.5
(30Hz)
Pr.271
(50%)
B
ON OFF ON
ON ON
Pr.272 Average current
(100%)
Value in parenthesis is initial value.
(A) Application parameters
Regenerating
Time
OFF
OFF
PARAMETERS
5
GROUP
A
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