3 reduced overcurrent due to output frequency, Reduced overcurrent due to output frequency, Table 31: overcurrent relative to time – NORD Drivesystems BU0500 User Manual
Page 165: 8 additional information
8 Additional information
BU 0500 GB-1013
165
230V devices: Reduced overload capacity (approx.) due to pulse frequency (P504) and time
Pulse frequency
[kHz]
Time [s]
> 600
60
30
20
10
3.5
3...8
110%
150%
170%
180%
180%
200%
10
103%
140%
155%
165%
165%
180%
12
96%
130%
145%
155%
155%
160%
14
90%
120%
135%
145%
145%
150%
16
82%
110%
125%
135%
135%
140%
400V devices: Reduced overload capacity (approx.) due to pulse frequency (P504) and time
Pulse frequency
[kHz]
Time [s]
> 600
60
30
20
10
3.5
3...6
110%
150%
170%
180%
180%
200%
8
100%
135%
150%
160%
160%
165%
10
90%
120%
135%
145%
145%
150%
12
78%
105%
120%
125%
125%
130%
14
67%
92%
104%
110%
110%
115%
16
57%
77%
87%
92%
92%
100%
Table 31: Overcurrent relative to time
Pos : 452 /Anleit ungen/8. / 9. Zusatzinfor mationen [BU 0500 / BU 0200]/ 8. 5. 3 R eduzi erter Überstrom aufgrund der Ausgangsfrequenz @ 0\ mod_1328188934696_388.doc x @ 14351 @ 3 @ 1
8.5.3 Reduced overcurrent due to output frequency
To protect the power unit at low output frequencies (<4.5Hz) a monitoring system is provided, with
which the temperature of the IGBTs (integrated gate bipolar transistor) due to high current is
determined. In order to prevent current being taken off above the limit shown in the diagram, a pulse
switch-off (P537) with a variable limit is introduced. At a standstill, with 6kHz pulse frequency, current
above 1.1x the nominal current cannot be taken off.
x f
( )
In_ 60s ec f
( )
In_ 1sec f
( )
f
0
2
4
6
8
10
12
14
16
18
20
0
0.5
1
1.5
2
2.5
I / I
N
Output frequency [Hz]
Prohibited region