Specifications

SED2 VFD Startup, Operation, and Maintenance Manual
74 Siemens Building Technologies, Inc.
Vdc Controller
Parameter Description Action Setting/ Default
P1240
Configuration of Vdc
Controller
Enables/disables Vdc
controller.
The Vdc controller dynamically
controls the DC link voltage to
prevent overvoltage trips on
high inertia systems.
Vdc-max automatically
increases ramp-down times to
keep the DC link voltage
(r0026) within limits.
0 = Vdc controller disabled
1 = Vdc-max controller
enabled
2 = Reserved
3 = Reserved
1. Press
to enter the
SED2 parameter mode
and to display r0000.
2. Press to advance
to parameter P1240.
3. Press
t
o access the
parameter values level.
4. Press
to advance
to desired value.
5. Press
to confirm
and save the setting.
Minimum: 0
Default: 1
Maximum: 3
Pulse Frequency
Parameter Description Action Setting/ Default
Pulse Frequency
Sets pulse frequency (kHz) of
power switches in SED2. The
frequency can be changed in
increments of 2 kHz.
Pulse frequencies > 4 kHz
selected on 380V to 480V units
reduce the maximum
continuous motor current.
1. Press
to enter the
SED2 parameter mode
and to display r0000.
2. Press
to advance
to parameter P1800.
3. Press
to access the
parameter values level.
4. Press
to advance
to desired value.
5. Press
to confirm
and save the setting.
Minimum: 2
Default:
Varies by model
(hp/voltage
dependent)
Maximum: 16
P1800
NOTES:
1. Minimum pulse frequency depends on P1082 (maximum frequency) and
P0310 (rated motor frequency).
2. At 4 kHz, full output curre
nt is obtained up to 50 degrees C (CT mode); over
50 degrees C, full output may be obtained at 8 kHz.
3. If silent operation is not absolutely necessary, lower pulse frequencies may
be selected to reduce SED2 losses and radio-frequency emissions.
4. Under certain circumstances, the SED2 may reduce the switching
frequency to provide protection against over-temperature.