Electrolux W3105H, Service Manual

Page: 98 / 170

23
23. Programme unit
24
438 9149-81/06
04.03
Service
Manual
Super imbalance measurement
Super imbalance measurement is the normal imbalance measurement. Its
task is to ensure that the machine is not overloaded during extraction, as
well as to ensure that the number of missed extractions is as small as
possible.
Super imbalance measurement starts a few seconds after the drum has
reached distribution rpm. The delay is there to allow the motor rpm to
Ôsettle down’ so that it is as stable as possible.
The magnitude of the imbalance is measured and compared first with a
fairly low imbalance limit value 1. If the imbalance exceeds this limit value,
the drum is slowed down to a lower rpm in order to achieve redistribution of
the clothes. It then accelerates again without stopping at the distribution
rpm again, after which a new imbalance measurement is carried out. The
number of attempts at limit value 1 may be set in the system data and can
also be altered in configuration 2. The value is normally set at 3.
If the imbalance is below the limit value, extraction starts at the extraction
speed specified in the programme after the distribution time has elapsed.
If the imbalance still does not drop below limit value 1 after three attempts,
the imbalance is instead compared with a slightly higher permitted
imbalance value, limit value 2. If the imbalance exceeds this limit value, the
drum is slowed down to a lower rpm in order to achieve redistribution of the
clothes. It then accelerates again without stopping at the distribution rpm
again, after which a new imbalance measurement is carried out. The
number of attempts at limit value 2 may be set in the system data and can
also be altered in configuration 2. The value is normally set at 2.
If the imbalance is suddenly lower than one of the two limit values, the
extraction starts with the extraction speed programmed in the programme.
The reason for the use of two limit values, both of which produce the same
extraction rpm, is that in order to look after the machine’s mechanism, it is
desirable in the first instance to extract with as low an imbalance as
possible.
In the same way as above, the imbalance is compared with a further two
limit values, limit value 3 and limit value 4. However, each of these gives a
reduced extraction rpm if the imbalance is below the limit value. The
number of attempts at limit values 3 and 4 may be set in the system data
and can also be altered in configuration 2. The value for each is normally
set at 2.