Siemens SINAMICS DCM Manual page 650

Maintenance
WARNING
Hazardous voltages are present in certain components of these electrical units during
operation.
Dangerous voltage levels may be present at the signaling relays at the customer's site.
Therefore, failure to handle the units properly can result in death or serious physical injury
as well as extensive property damage.
When performing maintenance on this unit, you should therefore observe all information
provided in this section as well as any notices attached to the product itself.
• Only qualified personnel who are familiar with all the safety instructions in this
description, as well as the installation, operating, and maintenance instructions, should
carry out maintenance work on this unit.
• Before carrying out visual inspections and maintenance work, it must be ensured that
the unit is disconnected from the AC power supply, disabled, and grounded. Before they
are shut down, both the converter unit and the motor are subject to dangerous voltage
levels; these may be present even when the converter unit's contactor is open.
• The TSE capacitors continue to carry dangerous voltage levels following disconnection.
For this reason, the unit should not be opened until an appropriate period of time has
elapsed.
Only spare parts approved by the manufacturer may be used.
The converter unit must be provided with extensive protection measures against
contamination in order to prevent voltage flashovers and, therefore, destruction. Dust and
foreign bodies, which are brought in by the cooling-air flow in particular, must be thoroughly
removed at certain intervals; this depends on the rate of accumulation of dirt, but should be
carried out at least every 12 months. The unit must be blown out with dry compressed air at
a maximum of 1 bar, or cleaned using a vacuum cleaner.
The screw connections (also the protective conductor connections) must be retightened
each time that maintenance work is carried out on the SINAMICS DCM.
Please note the following when working with converter units featuring increased air cooling:
The bearings for the fans are designed for an operating period of 30000 hours. The fans
must be replaced in good time to ensure the continued availability of the thyristor sets.
SINAMICS DCM DC Converter
Operating Instructions, 02.2015, A5E34763375/RS-AA/001
ac.maher.co.ir
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