Technical data

Manual – Gear Units and Gearmotors
95
7
Thermal characteristics (→ GM, → MM)
Project Planning for AC Motors
Cyclic duration
factor (cdf)
The cyclic duration factor (cdf) is the ratio between the period of loading and the duration
of the duty cycle. The duration of the duty cycle is the sum of times of operation and
times at rest and de-energized. A typical value for the duration of the duty cycle is ten
minutes.
Power increasing
factor K
Unless specified otherwise, the rated power of the motor refers to duty type S1 (100 %
cdf) according to IEC 60034 (EN 60034). If a motor designed for S1 and 100 % cdf is
operated in mode S2 "short-time duty" or S3 "intermittent periodic duty", the rated power
can be multiplied by the power increasing factor K specified on the nameplate.
In the case of extremely high counter torques and high mass moments of inertia (high
inertia starting), please contact SEW-EURODRIVE and provide the exact technical
data.
03135AXX
Figure 41: Duty types S1, S2 and S3
cdf =
total on-times (t1 + t2 + t3)
cycle duration (T)
• 100 [%]
Duty type
Power increasing
factor K
S2 Period of operation
60 min
30 min
10 min
1.1
1.2
1.4
S3 Cyclic duration factor (cdf)
60%
40%
25%
15%
1.1
1.15
1.3
1.4
S4...S10
The following information must be specified to determine the rated
power and the duty type: number and type of cycles per hour, starting
time, time at load, braking type, braking time, idle time, cycle duration,
period at rest and power demand.
On request