Start-up
Operating_Manual_Fan_KXE_04_en.docx
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The starting current for direct starting (delta starting) of the
motor can total 6 - 8 times the rated current.
Ensure appropriate electrical safeguarding
Ensure prompt continued connection from star to delta
starting to facilitate power-up of the fan.
Consider the current peak in this regard and ensure
appropriate electrical safeguarding.
The activation frequency of the motor totals a maximum
3 connection processes per hour.
Set the variable speed control as “slow-reacting” as possible
via the frequency converter in order to prevent fatigue
fractures due to rapid speed changes.
Consider sufficiently extensive time periods for:
- power-up up to operating speed or maximum speed
- powering down from operating speed or maximum
speed down to a standstill
- change of operating point, and thus the fan speed
Observe the ramp times which may not be fallen short of.
Refer to Table 9-2
Fan speed [rpm]
Ramp time [s]
750
38
1000
50
1200
60
1500
75
1800
90
3000
150
3600
180
9.3.1 Direct connection
9.3.2 Star-delta starting
9.3.3 Variable speed control
Table 9-2
Ramp times
