Lenze 8200 motec frequency inverter 0.25kW-7.5kW - Manual (Page 154)

Function library
Thermal motor monitoring, error detection
7−83
L
EDB82MV752 EN 5.2
The controller switches off with fault OC6, if the apparent motor current is higher than the rated motor
current over a longer period of 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. 7−16 Tripping characteristic of I 2 t monitoring
f Output frequency
t Time to trip
I
r
Rated controller current at a chopper frequency of 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 after approx. 60 s with fault OC6.
Tip
·
To prevent motors with forced ventilation from starting too early, this function can be
deactivated.
·
The current limits C0022 and C0023 only have indirect influence on the I 2 t calculation. It is
possible to prevent motor operation with a maximum of possible load with settings under
C0022 and C0023.
)
Note!
If the controller operates at increased rated power, the I 2 t monitoring starts if C0120
is set lower than 100 %.