Siemens SIMATIC ET 200pro - Figure 10-3: Cooling down Characteristics with and Without Idle Time

SIMATIC - ET 200pro motor starter
10-8 GWA 4NEB 950 5661-02 DS 04
Idle time (can only be parameterized for high feature motor starters)
The 'idle time' is a specified time for the cooling down characteristics after shut-
down by control functions at operating temperature, i.e. not due to overload.
When this time has elapsed, the thermal memory of the motor starter is
deleted and a cold start is possible.
This means that with the dimensions of the drive adapted accordingly a
higher switching frequencies are possible without exceeding the tripping limit of
the motor model.
Caution
Higher switching frequencies lead to greater motor heating.
If the motor dimensions are not adapted (heat class), motor protection is no
longer ensured.
The following schema shows the cooling down characteristics with and without
idle time:
Figure 10-3: Cooling down characteristics with and without idle time
Tripping limit
On
t
t
t
ϑ
ϑ
Overload tripping
Without idle time
With idle time
Motor
Off
No overload tripping
Idle time.
Thermal memory is deleted after the idle time
Tripping limit