Connecting
6.2 Electrical connection
1FE1 synchronous built-in motors
Hardware Installation Manual, 12/2016, 610.43000.40b
115
6.2.13
Voltage limitation
Note
EMF (Electro Motive Force) > 820 V
In a fault situation, a voltage limitation of the DC-link voltage on the converter is required.
The voltage limitation depends on the maximum EMF (induced chained voltage peak > 820
V).
A voltage limitation is required when the motor is operated with speed n > n
max inv
.
If the line voltage fails at maximum motor speed or if the drive converter pulses are canceled
as a result of the power failure, the synchronous motor regenerates a high voltage back into
the DC link. The voltage protection detects a DC-link voltage that is too high (> 820 VDC)
and short-circuits the three motor supply cables. The energy remaining in the motor is
converted into heat as a result of the short-circuit and causes the motor to quickly brake.
The VPM (Voltage Protection Module) is deployed as voltage limiter for SINAMICS S120.
Operation without voltage limiting
NOTICE
Danger of motor damage caused by exceeding the maximum speed
If a motor with EMF > 820 V is operated without voltage limitation, the maximum permitted
speed must be reduced.
•
Never operate the motor without voltage limitation.
•
Do not exceed the maximum permissible speed.
Calculate the maximum permissible speed for operation without voltage limitation with the
following equation:
k
E
= voltage constant, see Chapter "Technical data and characteristic curves" in the
Configuration Manual.
Voltage limitation with the Voltage Protection Module (VPM)
The Voltage Protection Module (VPM) is not included with the 1FE1 built-in motors.
●
The VPM ordering information is contained in Catalog NC 62.
