Uninterruptible power supply (option L53)
The uninterruptible power supply (UPS) ensures that when a power failure occurs, the drive
provides a controlled output current to trip the safety elements. The line is restored after the
short circuit has been removed. The auxiliary supply is not available when a short-circuit occurs
in the line. All auxiliary equipment, which does not permit a brief interruption, must be
appropriately buffered. This is used to provide the minimum supply for all open-and closed-
control components of the drive.
The uninterruptible power supply is designed for a buffer time of up to five minutes.
The drive may malfunction if you change the parameters.
Do not change the parameters.
Uninterruptible power supply messages
The uninterruptible power supply signals the following states to the higher-level control system:
Not ready for operation
If the uninterruptible power supply signals that a functioning battery status (battery "low") is
not guaranteed, then the internal battery should be replaced.
Anti-condensation heating (option L55)
The anti-condensation heating is used at low ambient temperatures and high levels of humidity
to prevent condensation from forming. The heating is controlled via a thermostat.
The number of anti-condensation heaters is set in accordance with the number of cabinet
The drive monitors the external auxiliary supply and outputs a message if it fails.
Safety instructions for maintenance (Page 83)
SINAMICS SM120 6SL38715
Operating Instructions 07/2015
The following fault exists:
Test every 40 hours automatically
UPS works in the battery mode