Figure 10-3: Cooling Down Characteristics With And Without Idle Time - Siemens SIMATIC ET 200pro Quick Manual
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Also See for SIMATIC ET 200pro:
- Operating instructions manual (545 pages) ,
- Original instructions manual (256 pages) ,
- Operating instruction (146 pages)
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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:
Motor
On
Off
Without idle time
ϑ
With idle time
ϑ
Figure 10-3: Cooling down characteristics with and without idle time
10-8
Idle time.
Thermal memory is deleted after the idle time
t
Tripping limit
Overload tripping
t
Tripping limit
No overload tripping
t
SIMATIC - ET 200pro motor starter
GWA 4NEB 950 5661-02 DS 04
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