Table of Contents
Advertisement
Group 25: Critical Freq
In some mechanical systems, certain speed ranges can cause resonance
problems. With this parameter group, it is possible to set up to two different
speed ranges that the ACS 140 will skip over.
Note! When the PID Control macro is used, critical frequencies are ignored.
Code Description
2501 CRIT FREQ SEL
Critical frequencies activation.
0 =
OFF
1 =
ON
2502 CRIT FREQ 1 LO
Critical frequency 1 start.
Note! If LOW > HI, no critical frequency lock-out will happen.
2503 CRIT FREQ 1 HI
Critical frequency 1 end.
2504 CRIT FREQ 2 LO
Critical frequency 2 start.
2505 CRIT FREQ 2 HI
Critical frequency 2 end.
Note! If LOW > HI, no critical frequency lock-out will happen.
Example: A fan system vibrates badly from 18 Hz to 23 Hz and from 46 Hz to
52 Hz. Set the parameters as follows:
1
= 18 Hz and
CRIT FREQ
LO
2
= 46 Hz and
CRIT FREQ
LO
f
output
[Hz]
52
46
23
18
Figure 7
Example of critical frequencies setting in a fan system with bad
vibrations at frequency ranges 18 Hz to 23 Hz and 46 Hz to 52 Hz.
1
CRIT FREQ
2
CRIT FREQ
f1H
f1L
f2L
23
18
46
= 23 Hz
HI
= 52 Hz
HI
f
REF
[Hz]
f2H
52
43
Advertisement
Table of Contents
