Current Characteristics - Lenze 8400 Hardware Manual

4.3

Current characteristics

The controller limits its maximally possible motor current under the following operating
conditions ("current derating"):
If the maximum heatsink temperature is exceeded
ƒ
– In this case, the controller switches independently from switching frequency mode
of 16 kHz to 8 kHz and from 8 kHz to 4 kHz (but not from 4 kHz to 2 kHz). This
function can be deactivated via C00144.
When the heatsink temperature continues to rise, the inverter output will be
inhibited and the error message "Trip" occurs. This also occurs when the switching
frequency reduction is deactivated.
In case of output frequencies f
ƒ
As a function of the switching frequency modes "fixed" or "variable"
ƒ
0
I
OUT
I
aM
I
aM02
I
aM04
I
aM08
I
aM016
0
Fig. 4-1
EDS84ASC552 EN 10.0
out
I
aM2
I
aM4
I
aM8
I
aM16
5 f [Hz]
out
Current derating characteristics
Derating curve depending on the fixed switching frequency

Derating curve depending on the variable switching frequency

I Output current
out
I Maximum output current (overload current)
aM
I Maximum output current (overload current) at different switching frequencies: 2kHz,
aMx
4kHz, 8kHz and 16kHz
I Maximum output current (overload current) at f
aM0x
frequencies: 2kHz, 4kHz, 8kHz, 16kHz
I Maximum output current (overload current) at a variable switching frequency
aMv
I Maximum output current (overload current) at f
aM0v
frequency
f Field frequency at the output U, V, W
out

Technical data
Current characteristics
< |5 Hz|
1
I
OUT
I
aM
I
aM0v
0 5 f [Hz]
out
= 0Hz and different switching
out
= 0Hz and a variable switching
out
I
aMv
8400GG084
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