Function library, Thermal motor monitoring i, T monitoring – Lenze E82xVxxxKxxxxx User Manual
Page 358: Setting tips
Function library
Thermal motor monitoring
I
2
t monitoring
l
358
EDS82EV903 EN 3.0
Adjustment
1. Calculate C0120. This value corresponds to a motor utilisation of 100 %:
C0120 [%] + I
r
I
N
@ 100 %
I
r
Rated motor current
I
r
Rated controller current at switching frequency 8 kHz
2. If you decrease C0120 on the basis of the value calculated, the monitoring already
responds at a motor utilisation < 100 %.
3. If you increase C0120 on the basis of the value calculated, the monitoring only
responds at a motor utilisation > 100 %.
The controller switches off with error OC6 if the apparent motor current is greater than the
rated motor current for a longer time.
60
180
240
300
360
t [s]
0.5
0
0
1.0
1.5
2.0
C0054
I
r
120
f = 0 Hz
f = 20 Hz
f > 40 Hz
I x 100 %
I
r
N
C0120 <
I x 100 %
I
r
N
C0120 =
I x 100 %
I
r
N
C0120 >
8200vec523
Fig. 10−16
Tripping characteristic of I
2
t monitoring
f
Output frequency
t
Release time
I
N
Rated controller current at switching frequency 8 kHz
I
r
Rated motor current
C0054
Apparent motor current
Example:
C0120 +
I
r
I
N
@ 100 %
C0054 = 1.5 x rated motor current
The controller switches off at output frequencies f > 40 Hz with error OC6 after
approx. 60 s.
Setting tips
ƒ
To avoid an early response in the case of forced ventilated motors, deactivate the
function, if necessary.
ƒ
The current limits C0022 and C0023 only have an indirect effect on the I
2
t
calculation. However, you can prevent the motor from being actuated at the
maximum possible utilisation by the settings of C0022 and C0023.
)
Note!
If the controller is actuated at an increased rated power, the I
2
t monitoring can
respond if C0120 is set to a smaller value than 100 %.