Air Conditioner User Manual

Startup Procedures
Siemens Building Technologies, Inc. 37
Pulse Frequency
Parameter Description Action
Setting/
Default
P1800
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 = 4
Default =
Varies by
model
(hp/voltage
dependent)
Maximum = 16
NOTES:
1. Minimum pulse frequency depends on P1082 (maximum frequency) and P0310 (rated motor
frequency).
2. At 4 kHz, full output current 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.