Stall Prevention Operation - Mitsubishi Electric FR-A820-00046 (0.4K) Instruction Manual

• When frequency jump ranges overlap, the lower limit of the lower jump range and the upper limit of the upper jump range
are used.
• When the set frequency decreases and falls within the jump range, the upper limit of the jump range is the set frequency.
When the set frequency increases and falls within the jump range, the lower limit of the jump range is the set frequency.
Pr.36
Pr.35
Pr.33
Pr.34
Pr.32
Pr.552
Pr.31
Pr.552
0
NOTE
• During acceleration/deceleration, the running frequency within the set area is valid.
• If the setting ranges of individual groups (1A and 1B, 2A and 2B, 3A and 3B) overlap, Parameter write error (Er1) occurs.
• Setting Pr.552 = "0" disables frequency jumps.
• If a jump frequency that exceeds Pr.1 (Pr.18) Maximum frequency is set for the 3-point frequency jump, the maximum
frequency setting is the set frequency. If the set frequency is less than the jump frequency Pr.2 Minimum frequency, the jump
frequency is the set frequency. (The set frequency can be equal to or lower than the frequency lower limit.)
Example with 6-point frequency jump
Output frequency
Maximum
frequency
0
Maximum frequency and frequency jump
Parameters referred to
Pr.1 Maximum frequency, Pr.2 Minimum frequency, Pr.18 High speed maximum

5.10.11 Stall prevention operation

Magnetic flux Magnetic flux Magnetic flux
V/F V/F V/F
This function monitors the output current and automatically changes the output frequency to prevent the inverter from shutting
off due to overcurrent, overvoltage, etc. It can also limit the stall prevention and fast-response current limit operation during
acceleration/deceleration and power/regenerative driving.
This function is disabled during Real sensorless vector control, Vector control and PM sensorless vector control.
• Stall prevention:
If the output current exceeds the stall prevention operation level, the output frequency of the inverter is automatically
changed to reduce the output current. Also, the second stall prevention function can limit the output frequency range in
which the stall prevention function is enabled.
• Fast-response current limit:
If the current exceeds the limit value, the output of the inverter is shut off to prevent an overcurrent.
Jump range
Jump range
Input set frequency
Output frequency
Pr.552
Minimum
frequency
Pr.552
Set frequency
Set frequency after
frequency jump
Pr.32
Pr.31
0
Input set frequency
Pr.552
Pr.552
0 Set frequency
Minimum frequency and frequency jump
frequencypage 407
5.10 (H) Protective function parameter
Pr.552 Jump range
Pr.552
5. PARAMETERS
1
2
3
4
5
6
7
8
9
10
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