8.5.3.5
Fan monitoring
Monitoring the fan ensures that the device functions safely. If the cooling is insufficient, an
alarm is output.
8.5.3.6
Speed monitoring with incremental encoder
Permanent speed monitoring enables motor control without an encoder. You can upgrade with
additional incremental encoders under the following conditions:
● When high-performance applications, such as bearing control, require a permanent speed
control.
● For long-continuing applications with low speeds.
8.5.3.7
Automatic restart
After the power fails and returns, the drive is automatically switched on again, irrespective of
the length of the power failure. Alarms are acknowledged automatically and the drive is
restarted.
Prerequisites
The following general conditions must be satisfied in order that the drive can be switched on:
● The auxiliary supplies must not fail.
● The power supply for the fans, coolant pumps, and the open-loop/closed-loop controllers
must be maintained.
If the main infeed fails, the pulse block is initiated. The DC link is supported for a short time using
the precharge.
Starting the drive from standstill
This function is suitable for drives with low moments of inertia and load torques that allow the
drive to come to standstill within seconds, e.g. pump drives with a head of water.
Starting the drive with the "flying restart" function
This function can also be activated as follows: The function is suitable for drives with high inertia
loads (e.g. fan drives). This function can be used to switch the drive to the motor that is still
rotating.
Operation
8.5 Functions
SINAMICS SM150 6SL3815-7NP41-0AA1
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Operating Instructions Rev.201910281301 EXAMPLE