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5
Motor control (MCTRL)
5.14
Monitoring
300
Lenze · 8400 HighLine · Reference manual · DMS 12.0 EN · 06/2017 · TD23
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Adjustment of the motor utilisation meter
The motor utilisation meter for indicating the motor load in
begins to count when the
apparent motor current (
) is greater than the motor overload setting (
The Motor overload setting (
) is calculated as follows:
• If you reduce
starting from the calculated value, the motor utilisation meter will already
be counted up before the rated overload threshold is reached.
• If you increase
starting from the calculated value, the motor utilisation meter will not
be counted up until the rated overload threshold is reached.
[5-34] Tripping characteristic of the I
2
xt monitoring
Example in Figure
:
r
/I
rated
x 100 % =
x 100 %
= 150 % rated motor current
• After approx. 60 seconds,
has reached the final value (100 %) at output frequencies
f > 40 Hz.
• The inverter outputs the "
" error message and triggers the response set
(default setting: "Warning").
f: Output frequency
t: Release time
I
N
: Rated device current at a switching frequency of f = 8 kHz
I
r
: Rated motor current (see nameplate of motor)
: Apparent motor current
: Motor overload setting
C00120
Rated motor current (C00088)
Rated device current (C00098)
------------------------------------------------------------------------------
100 %
⋅
=
60
1
8
0
2
4
0
300
360
t
[
s
]
0
.
5
0
0
1
.
0
1
.
5
2
.
0
C0005
4
I
r
120
f
=
0
Hz
f
=
20
Hz
f
> 4
0
Hz
I x 100 %
I
r
N
C00120 <
I x 100 %
I
r
N
C00120 =
I x 100 %
I
r
N
C00120 >