Siemens 6SR41 series Product User Manual page 96

Product Description
5.3 Cabinet Details
cell. The male connecting bus is located in line with the exhaust air of the cell. For systems
with mechanical cell bypass, the contactors are mounted on an additional bus, located in the
rear common exhaust air plenum. All of the bus and the contactors are therefore forced-air
cooled, but at an elevated ambient due to cell and transformer losses. Two phases of each
cell's inputs are fused. A common fuse block is located at the front of the transformer
section. The fuse ambient is the same as the drive's ambient air temperature.
If redundant blowers are required, a cover plate is removed from the top of the enclosure
and a dual blower cage assembly is installed. Dampers are installed at the base of the
redundant blower cage to prevent reverse air flow. The dampers are opened by air pressure
differential and closed by springs. The blower cage assembly design consists of a steel
frame with mesh on three sides (duct interface jobs require alternative pre-engineered
blower cage). Air is exhausted out of the front and sides of the cage. Air is not exhausted
towards the back or top of the drive. A fault contact is wired into the NXG II control I/O. If a
redundant blower is selected, the control cycles the blower periodically, and toggles them
upon receiving a FAULT feedback from the blower.
Note
The control removes power via a starter for a brief time following a FAULT signalization,
according to the blower manufacturer's recommendation. See Figure "GenIV 500 mm EC
Blower and Cage Cutaway" for a view of the blower cage and EC blower.
Figure 5-27
94
GenIV EC Blower and Cage Cutaway
Operating Instructions, Version AE 12/2009, A5E01454341C
Product User Manual