84 · vacon
Description of parameters
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5
Example Air Cooled AFE unit 460 A 500 Vac :
System Rated Current: 385 A (I
h
)
Current Limit: 693 A (I
s
)
Short Circuit Level:
√2 1.25
319 %
Short Circuit detection
Three phase
Fault: F91 Short Circuit
P
SystemRatedCurre
P
Current Limit I
SC
P
Short Circuit Level
P
ShortCircuitTime
V
Over Current Trip Limit
M
Current
4 * I
h
I
h
I
th
or I
s
(I
sc
/I
h
) * 1,77
Figure 30.
2.6.1.3
Short Circuit Time
The maximum time that the drive can operate against the current limit.
NOTE! The function requires a uGrid Licence (P3.2 uGrid Licence)
2.6.1.4
High Frequency Current Limit
In normal motoring drives I
s
is for starting current. In Grid Converter case I
s
must be
enabled separately for short circuit current if current levels above I
h
50 % over load
currents are needed for air cooled units. Liquid cooled units I
th
is always the maximum
limit.
The parameter can be disabled when a licence key has been given and the drive is
connected to DC (INU unit). If connected to AC grid (FC unit), this parameter must be
kept at 0 / Enable.
NOTE! The function requires a uGrid Licence (P3.2 uGrid Licence)
