Synchronous motors (PMSM) – Manual with installation instructions
20
B 5000 en-2621
2.4.4 Frequency inverters and encoders
The motors must only be operated with suitable frequency inverters.
For energy-efficient operation, the frequency inverter must detect the position of the rotor. For this,
different options with and without an encoder are possible, see also
The drive was qualified for operation with link circuit inverters according to DIN EN 60034-18-41
(2014).
Please also observe the operating instructions for the frequency inverter in use.
The insulation system used by NORD consists of suitable varnished copper wire, phase insulation,
homogeneous impregnation and groove lining as insulation against earth. The insulation system in the
standard version is designed for the increased requirements of operation with link circuit inverters.
The maximum permissible FI input voltage is 500 V +10%. Link circuit voltages in excess of 750 V DC
are not permissible. Peak voltages due to the system of inverter, cable and motor must not exceed the
following values when the motor is warm due to operation.
Figure 3: Permissible impulse voltages depending on the voltage rise time
If the values are outside of the permissible range, du/dt or sine wave filters may be used. Observe the
additional voltage drop.
The cable lengths shown in the diagram are for guidance only and may deviate depending on the
specific conditions.
Im
pul
se
v
ol
tag
e [
V]
Voltage rise time [µs]
