Lenze 8400 - Page 300

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 C00066
begins to count when the
apparent motor current (C00054
) is greater than the motor overload setting (C00120).
The Motor overload setting (C00120
) is calculated as follows:
•If you reduce C00120
starting from the calculated value, the motor utilisation meter will already
be counted up before the rated overload threshold is reached.
•If you increase C00120
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 [5-34]:
C00120 = I
r
/I
rated
x 100 % = C00088/C00098 x 100 %
C00054
= 150 % rated motor current
• After approx. 60 seconds, C00066
has reached the final value (100 %) at output frequencies
f>40Hz.
• The inverter outputs the "oC6: I2xt overload motor
" error message and triggers the response set
in C00606
(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)
C00054
: Apparent motor current
C00120
: Motor overload setting
C00120
Rated motor current (C00088)
Rated device current (C00098)
------------------------------------------------------------------------------
100 %⋅=
60
180
240
300
360
t [s]
0.5
0
0
1.0
1.52.0
C00054
I
r
120
f = 0 Hz
f = 20 Hz
f >40 Hz
I x 100 %
I
r
N
C00120 <
I x 100 %
I
r
N
C00120 =
I x 100 %
I
r
N
C00120 >