Siemens SIMOTICS L-1FN3 - Page 112

Configuration
5.2 Configuring workflow
1FN3 linear motors
110 Configuration Manual, 10/2018, 6SN1197-0AB86-0BP2
Example
The 1FN3300-2WC00-0AA1 motor is to be run with maximum current from the cold
condition.
● I
MAX
= 39.2 A, I
N
= 12.6 A; this results in ν = 9.679
● t
TH
= 120 s
The motor can be operated for a maximum of 13 s at maximum current.
Intermittent duty S3
With intermittent duty S3, periods of load time Δt
B
with constant current alternate with
periods of downtime Δt
S
with no current feed. The motor heats up during the load time and
then cools down again while at standstill. After a sufficient number of duty cycles with cycle
duration Δt
Spiel
= Δt
B
+ Δt
S
, the temperature characteristic oscillates between a constant
maximum value T
o
and a constant minimum value T
u
; see figure below.
Figure 5-4 Current and temperature characteristic for intermittent duty S3
For currents I
N
< I
M
≤ I
MAX
, it is not permissible that the rms current exceeds the rated current:
In this respect, the cycle duration should not exceed 10% of the thermal time constant t
TH
.
If a longer cycle duration is necessary, please contact your local Siemens office.