Converter Operation; Operation On A Converter With A Low Pulse Frequency; Maximum Peak Voltage At The Motor Terminals - Siemens SIMOTICS FD 1LL1 Operating Instructions Manual

Electrical connection
6.5 Connecting the auxiliary circuits
6.5.5

Converter operation

The following chapter is relevant only if the machine has been ordered for converter operation.
Note
The order number shows whether the machine was ordered for converter operation. In this
case, digits 1, 2, 3 or 4 is located at the 6th position of the order number.
Dangerous voltage via the converter
As long as the feeding converter is switched on, or the DC link of the converter is not
discharged, there can be a voltage at the motor terminals even when the rotor is not moving.
The voltage is up to 1000 V, depending on the converter type.
Ensure that the five safety rules (Page 15) are followed before working on the motor.
6.5.5.1

Operation on a converter with a low pulse frequency

NOTICE
Increased motor temperature
If the pulse frequency is less than the rated pulse frequency, then increased motor losses
occur. This results in a higher motor temperature.
● Reduce the power to prevent exceeding the temperature class and to avoid consequential
● Contact the Service Center if necessary.
6.5.5.2

Maximum peak voltage at the motor terminals

The maximum peak voltage values at the motor terminals are listed in the table as limit values
for the insulation system:
Table 6-6
Rated motor voltage [V]
≤ 500 V
> 500 to 690 V
88
WARNING
premature thermal aging of the insulation.
Maximum peak voltage at the motor terminals
Maximum peak voltage at the motor terminals Û
Conductor - conductor
1500 V
Rise time 0.5 μs
2250 V
Rise time 0.4 μs
Conductor - ground
1100 V
Rise time 0.5 μs
1500 V
Rise time 0.4 μs
Operating Instructions 04/2016
max
DC link
750 V
1125 V
SIMOTICS FD 1LL1