Cooling; Table 5- 17 Blower Components (4160 V Drives) - Siemens 6SR41 series Product User Manual

Product Description
5.3 Cabinet Details
reactor. The line reactor is then connected to a motor starter that is controlled through the
SOP of the NXG II controller. The output of the motor starter connects to a quick disconnect
plug associated with that blower. Fault logic is fed back through the plug back into the I/O
system of the NXG II controller.
The default SOP logic is such that upon energizing the control power, Blower #1 (TBLW1 &
CBLW1 for 6600 V drives; TBLW1/2, CBLW1/2 for 10000 V drives) is operated immediately.
The fault logic is ignored for a short duration to allow the blower to soft start up. After this
duration, if the SOP logic controller detects a FAULT feedback, the redundant blower(s) is
started or else the drive trips on a ALL BLOWERS LOST fault, and the drive must be
manually reset. The starter voltage is automatically removed for a brief duration to allow the
EC blower(s) to reset. If redundant blowers are equipped on the drive, the blowers are
cycled on a periodic basis (typically every 7 days). The 2.5% line reactors are used to
decouple the EC blower from brief line disturbances; in addition, the reactors filter the current
draw from the blower and make it more sinusoidal. When using an AC blower, the 2,5% line
reactors are not required.
5.3.7

Cooling

An extremely important part of the installation process is making provisions for exhausting
the heat that is generated by the operation of the drive. Although the GenIV drive is highly
efficient, there may be as much as a 4.0% energy loss emitted in the form of heat from inside
the system cabinetry. This heat must be transmitted to the outdoor air or into the structure of
the building at a rate fast enough to prevent the ambient temperature from rising above the
rated conditions stated in Chapter 3.
Blowers # 1 and # 2
The GenIV blower cages are located on the roof of the enclosure. Only one blower is
required to operate the drive. The cage assemblies are typically removed and packaged
separately for shipment. All electrical connections between the drive and blower are made
via a quick disconnect harness for ease of installation. The GenIV blower cage uses a rear
tongue and groove lip and two front flange-mounted fasteners so that it is easily front-
access-maintainable following installation. Components in these sections include:
Table 5- 17 Blower Components (4160 V Drives)
Component Label
BLW1
RBLW1*, DBLW1*
1)
BLW2
RBLW2*, DBLW2*
1)
* Resistor and Zener diode form a clamp circuit to command the blower speed (See table below for blower speed
settings). However, if a duct Interface is required, these components are removed and the command jumpers
directly to the +10 VDC for a 100 % speed demand.
For AC blowers, the blower command (resistor and zener) are not required.
1)
92
Part Description
Blower #1
Blower command; resistor and zener diode
Blower #2 (optional)
Blower command; resistor and zener diode (optional)
Operating Instructions, Version AE 12/2009, A5E01454341C
Product User Manual