NORD Drivesystems BU0230 User Manual
Page 30
Functional safety with NORD SK 200E frequency inverters
30
BU 0230 GB-2712
Size 4:
Input
circuitry
I
/
O
Control
Driver
µ
C
T
5
T
6
T
3
T
4
T
1
T
2
U
V
W
M
L
1
L
2
L
3
Logic
=
=
=
=
G
N
D
2
4
V
=
=
Control voltage
Internal voltage (Primary power)
3x High
1x Low
GND_SH
24V_SH
Frequency Inverter
Emergency
Option "safe pulse block"
stop
The semiconductor switches of the inverter (T1 to T6) are controlled by a highly complex pulse pattern. This
pulse pattern is generated by the microcontroller (µC) and amplified by the driver. The drivers convert the logic
signals on the control voltages of the semiconductor switch. The semiconductor switches are switched via the
control voltage and the pulse pattern is amplified and applied to the motor terminals. Due to the low-pass effect
of the motor, a three-phase pulse width modulated sine wave voltage - a three-phase system, results from the
pulsed voltage. The motor generates a torque.