Operators Manual
ALS 221
Release 7/04
Page 17
Labelling
3.3
Using the FEED key to measure the label pitch
Each time the FEED key is used to feed the label web the machine measures the distance to
the next leading label edge and stores this measurement internally as the label pitch. The label
pitch is the distance from one leading label edge to the next leading label edge.
The internally stored value for the label pitch is used:
y
to stop the label web in the correct position
y
for the missing label function which stops the label web in the correct position even if a label
is missing from the label web.
When changing label rolls it is therefore necessary to press the FEED key twice so that the
machine can store the new label pitch. The first press of the FEED key will move the next lead-
ing label edge under the gap sensor, the second press will move the web by one full label pitch
and the correct label pitch value will then be stored.
The internally stored label pitch is retained when the machine is turned off.
3.4
Missing label function and web breaks
The missing label function stops the label web in the correct position even when a label is miss-
ing from the label web. If there are more than 3 missing labels from the web then the machine
will stop and give the error message E__1.
If the label web has broken or come to an end then the machine will no longer be able to find
the next leading label edge and so after more than 3 signals from the product sensor the error
message E__1 will also be generated.
3.5
Control of the labelling
The machine carries out the labelling of your products fully automatically. Check now and then:
y
if there is still enough labelling material on the unwind roll
y
if an error has been displayed and the labeller no longer carries out labelling
y
if the labels are being placed accurately onto the products. Changes of the label position
can be made with the 2 position keys.
Operating is simpler if you use the optional OD-control, which checks the diameter of the mate-
rial roll and triggers an error message when there are not enough labels on the roll anymore. If
the error output is connected to an alarm indicator, an optic or acoustic signal can be gener-
ated.
