Operating Instructions

Startup Procedures
Siemens Building Technologies, Inc. 39
Parameter Description Action Setting/Default
P1120
Ramp-up Time
0s to 650s
1. Press
to advance to
parameter P1120.
2. Press to access the
parameter values level.
3. Press
to advance it desired
value.
4. Press
to confirm and save
the setting.
Site Setting
Default = 10
Typical fan = 120s
Typical pump = 30s
NOTES:
1. Setting the ramp-up time too short can cause the SED2 to trip (F0001 over current, F0002 overvoltage, or
F0003 under voltage).
2. If using an external frequency setpoint with set ramp rates (such as from a PLC), achieve optimum SED2
performance by setting ramp time (P1120 and P1121) slightly shorter than those of the PLC.
P1121
Ramp-down time
0s to 650s
1. Press to advance to
parameter P1121.
2. Press
to access the
parameter values level.
3. Press to advance it desired
value.
4. Press
to confirm and save
the setting.
Site Setting
Default = 30
Typical fan = 120s
Typical pump = 30s
NOTES:
1. Setting the ramp-up time too short can cause the SED2 to trip (F0001 over current, F0002 overvoltage, or
F0003 under voltage.
2. If using an external frequency setpoint with set ramp rates (such as from a PLC), achieve optimum SED2
performance by setting ramp times (P1120 and P1121) slightly shorter than those of the PLC.