# Avoiding Machine Resonance Points (frequency Jump) - Mitsubishi Electric FR-A820-00046 (0.4K) Instruction Manual

Fr-a800 series.

CAUTION
• Note that when Pr.2 is set to any value equal to or higher than Pr.13 Starting frequency, simply turning ON the start
signal runs the motor at the frequency set in Pr.2 even if the command frequency is not given.
Parameters referred to
Pr.13 Starting
frequencypage
Pr.15 Jog
frequencypage 390
Pr.125 Terminal 2 frequency setting gain frequency, Pr.126 Terminal 4 frequency setting gain
5.10.10 Avoiding machine resonance points (frequency
jump)
When it is desired to avoid resonance attributable to the natural frequency of a mechanical system, these parameters allow
resonant frequencies to be jumped.
Pr.
31
Frequency jump 1A
H420
32
Frequency jump 1B
H421
33
Frequency jump 2A
H422
34
Frequency jump 2B
H423
35
Frequency jump 3A
H424
36
Frequency jump 3B
H425
552
Frequency jump range
H429
 3-point frequency jump (Pr.31 to Pr.36)
• Up to three areas may be set, with the jump frequencies set to either the top or bottom point of each area.
• The settings of frequency jumps 1A, 2A, 3A are jump points, and operation is performed at these frequencies in the jump
areas.
Pr.36
Pr.35
Pr.33
Pr.34
Pr.32
Pr.31
Example 1) To fix the frequency to 30 Hz in the range of 30 Hz to 35 Hz, set 35 Hz in Pr.34 and 30 Hz in Pr.33.
Pr.34: 35 Hz
Pr.33: 30 Hz
Example 2) To jump the frequency to 35 Hz in the range of 30 Hz to 35 Hz, set 35 Hz in Pr.33 and 30 Hz in Pr.34.
Pr.33: 35 Hz
Pr.34: 30 Hz
 6-point frequency jump (Pr.552)
• A total of six jump areas can be set by setting the common jump range for the frequencies set in Pr.31 to Pr.36.
408
5. PARAMETERS
5.10 (H) Protective function parameter
363,
page 364
Name
Initial value
9999
9999
Frequency jump
Input set frequency (Hz)
frequencypage 482
Setting range
0 to 590 Hz,
1A to 1B, 2A to 2B, 3A to 3B are frequency jumps (3-point jump).
9999
9999: Function disabled
0 to 30 Hz
Set the jump range for the frequency jumps (6-point jump).
9999
3-point jump
Description