Operating Instructions – Explosion-Proof AC Motors DR63/eDR63, DVE250/280
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6
Permitted duty types
Duty Types and Limit Values
Frequency inverters from SEW-EURODRIVE
When using frequency inverters from SEW-EURODRIVE at line voltages of up to 500 V,
the maximally permitted limit values of the motors are met.
The maximum permitted motor cable length is 100 m.
A braking resistor and 4Q startup are mandatory. This prevents the DC link voltage from
increasing to an unacceptable level in case of a fault in 1Q operation. External compo-
nents, e.g. output choke, must not be used.
Regeneration
The regenerative power supply module of MOVIDRIVE
®
can be used with the neces-
sary options without restrictions. The regenerative power supply unit prevents high DC
link voltages and ensures that the limit values are not exceeded.
Frequency inverters from third party manufacturers
If the maximum permitted limit values cannot be met with frequency inverters from other
manufacturers, you must take limiting measures. Consult the manufacturer of the fre-
quency inverter.
IT network
In an IT system, an insulation fault between a phase and ground is tolerated. The ground
connection of the motor could mean that the maximum permitted limit value for phase-
to-ground of 1200 V is exceeded in regenerative operation. To prevent this effectively,
you have to install suitable protection elements between the frequency inverter and the
motor. Usually, sine filters are installed between frequency inverter and motor for this
purpose. For detailed information about component selection and wiring, please contact
the manufacturer of the frequency inverter.
INFORMATION
The maximum permitted rated motor voltage for frequency inverter operation is 500 V.
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