User Manual

4 5
■ Energy-saving technology
and functions
Requirements for modern heating, ven-
tilation, and air conditioning systems:
maximum room comfort with minimum
energy consumption. For this, SED2
variable speed drives are an important
component. In combination with fans
and pumps, they offer a high energy-
and cost-saving potential.
SED2 exactly adjust to the delivery rate
of fan or pump motors in an energy-
efficient way. Automatic switching to
the integrated bypass function in nomi-
nal load operation reduces the electric
switching loss of the variable speed
drives. The hibernation function that is
based on the PID controller reduces en-
ergy consumption by switching the SED2
off when demand is low. The seven-days
time switching function can be realized
with the advanced operator panel AOP
and helps to save energy and costs as
well.
■ Low Harmonic Technology
Typical applications for the SED2 variable
speed drives are variable torque fans and
pumps. To reduce harmonic currents on
the AC line, Siemens has developed a
technology for use with the SED2 that
does away with extra components such
as AC line reactors. The technology is
called Low Harmonic Technology.
Tests reveal that the Low Harmonic
Technology clearly leads to a reduction
of low order harmonic currents on the
AC line. In contrast to standard variable
speed drives, the SED2 deliver good test
results without using AC line reactors.
Harmonics characteristics of the SED2
are comparable or even better than those
of variable speed drives equipped with
extra AC line reactors or DC link chokes.
Benefits of the Low Harmonic Technology
include:
– Direct cost savings since AC line
reactors are not needed
– Lower maintenance costs since the
motors produce less heat, leading
to longer motor life cycles
– Added protection for sensitive
equipment such as computers
and communication modules, etc.
– Reduced quantity of blind current
and reduction of potential compen-
sation costs
Typical speed-torque characteristic of a variable torque pump or fan
■ More benefits for increased
efficiency
The commissioning assistant of the
parameterizing software EasyComm
supports the user step-by-step and thus
reduces time, effort, and costs for com-
missioning. Thanks to the intuitive user
guidance, even complex PID controller
tasks can be easily parameterized in
just a few seconds.
In addition, the software also includes a
comprehensive application library. The
applications can be adjusted to customer
requirements easily and quickly.
Highlights
■ Drastic energy savings thanks to
demand-controlled, bypass, hiber-
nation as well as time switching
functions
■ Minimized mains harmonics thanks
to Low Harmonic Technology
■ Drastic time and cost savings thanks
to commissioning assistant and
application libraries
Saving costs with less energy
consumption and high efficiency
Comparison of THDI (Total Harmonic Distortion Current) –
overall harmonic power distortion
100
80
60
40
20
0
THDI (%)
SED2
Typical 6-pulse VSD
with 5%
line
reactor
with
DC link
choke
with 3%
line
reactor
No
filtering
more
than
120%
100
50
0
10050
Energy Consumption
Ventilation %
Volume Flow %
Variable
Speed
Drive
Outlet Damper
Energy Saving Area