Technical data

Manual
Double Sheet Detector R1000 series E20
System description
B0046991 / Rev. 1.6
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ROLAND ELECTRONIC GmbH · Otto-Maurer-Str. 17 · DE 75210 Keltern · Phone [phone] · Fax [phone]
3.4.2 Program parameters
The sensor is operated with an electro magnetical method – called “P“ measurement. For the P
measurement a compensation curve for linearization exists. The compensation curve fits to ST37
steel. Other steel alloys resp. magnetical materials deviate from this curve. This causes measuring
results which can deviate for more than 5% from the real sheet thickness. In such cases it is useful
to calibrate the unit (later merely called “Teach-In“).
In order to avoid frequent Teach-In procedures for different materials and thicknesses, the unit
provides for 255 program memories. Every such memory consists of a data set with the following
parameters.
“Sensor number“
Entry of the selected sensor (/sensor sequence) for multi-channel systems (e.g. E20-4P…).
“Nominal measure“
Changes the nominal measure. It can be shown in mm or inch.
Default setting either 0.03mm or 0.001 inch.
“TO“ and “TU“
Changes the limit values for the lower and upper switching threshold. The values can be entered
either in % or in mm/inch. On these thresholds the status signals depend. In a window comparator
the three signals will be generated from the measuring signal.
The signal “0-sheet“ is generated when the measuring signal falls short of the lower switching
threshold. The lower switching threshold TU can be set from 1...99%. The signal “2-sheet“ is
generated when the upper switching threshold is exceeded. The upper switching threshold TO can
be set from 100...150%. If the measuring value is within both limits, the signal “1-sheet“ is
generated.
2
1
0
Signal
Obere Schaltschwelle
Upper switching threshold
Untere Schaltschwelle
Lower switching threshold
a
b
c
TO
TU
a
b
c
TO
TU
Signal range for 0-sheet
Signal range for 1-sheet
Signal range for 2-sheet
switching threshold for upper limit
switching threshold for lower limit
Fig. 13: Visualisation of switching thresholds
The preset values (TO=120% resp. TU=80%) should only be changed under the following aspects:
1. the 1-sheet range becomes restricted, since the measuring values are very stable. Thus the
process security increases. The restriction can be done by decreasing the TO value, by
increasing the TU value, or both.
2. the 1-sheet range becomes extended for a time. Thus the process security decreases. Such an
action should only be performed in exceptional cases, the user has to decide about that.
Extending the 1-sheet range is commonly considered due to mechanical problems (air gap,
uneven sheets). This measure prevents the machine from standstill, until the mechanical
problem is solved.