8
Additional information
BU 0500 GB
Subject to technical alterations
153
8.5.4 Reduced output current due to mains voltage
The devices are designed with thermal characteristics according to the nominal output currents. Accordingly,
for lower mains voltages, higher currents cannot be taken off in order to maintain the stated power constant.
For mains voltages above 400v there is a reduction of the permissible continuous output current, which is
inversely proportional to the mains voltage, in order to compensate for the increased switching losses.
1.2
0.4
k
Unetz
Unetz
(
)
480
320
Unetz
320
340
360
380
400
420
440
460
480
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
Mains voltage [V]
I / I
N
8.5.5 Reduced output current due to the heat sink temperature
The temperature of the heat sink in included in the calculation of the reduction of output current, so that at low
heat sink temperatures, a higher load capacity can be permitted, especially for higher pulse frequencies. At
high heat sink temperatures, the reduction is increased correspondingly. The ambient temperature and the
ventilation conditions for the device can therefore be optimally exploited.
8.6 Operation with FI circuit breakers
SK 5xxE frequency inverters are designed for operation with a 30mA all-current sensitive FI circuit breaker. If
several frequency inverters are operated on a single FI circuit breaker, the leakage currents to earth must be
reduced. Further details can be found in Section 2.8.6 – 2.8.7.
