
36
Operating Instructions – Explosion-Proof AC Motors DR63/eDR63, DVE250/280
6
Permitted duty types
Duty Types and Limit Values
6
Duty Types and Limit Values
6.1
Permitted duty types
6.1.1
Permitted voltage load for frequency inverter operation
Operating SEW motors on frequency inverters is permitted if the pulse voltages at the
motor terminals indicated in the following figure are not exceeded.
Motor type and
equipment cate-
gory
Protection against impermissi-
bly high temperatures exclu-
sively through
Permitted duty type
eDR63
II2G
II2D
II2GD
Motor protection switch
•
S1
•
Heavy starting not possible
1)
1) Heavy starting is present when a motor protection switch that was properly selected and set for normal
operating conditions trips during the acceleration time. This is usually the case when the acceleration time
is > 1.7 x t
E
time.
Motor protection switch and PTC
thermistor temperature sensor
(TF)
•
S1
•
Heavy starting not possible
DR63
DVE250/280
II3GD/II3D
Motor protection switch
•
S1
•
Heavy starting not possible
PTC thermistor (TF)
•
S1
•
Heavy start
•
Frequency inverter operation according to
specifications
•
with soft start units
[A]
Permitted pulse U
LL
in V
[B]
Rise time in µs
[1]
Permitted pulse voltage
0
200
400
600
800
1000
1200
1400
1600
1800
2000
[A]
[B]
0
0,2
0,4
0,6
0,8
1,0
1,2
1,4
[1]
NOTE ON EXPLOSION PROTECTION
The permitted maximum PE voltage of 1200 V must not be exceeded in IT system
operation even in the event of an error.
NOTE ON EXPLOSION PROTECTION
If the permitted pulse voltage is exceeded, you have to provide for according mea-
sures to limit the pulse voltage. Consult the manufacturer of the frequency inverter.
P
i
f
kVA
Hz
n