BDK-1.3, BDK/FS-, …/FP-, …/PN-, …/OB-1.3 Sheet Meta Thickness / Doub e Sheet Detection
Ref. no. 20.05-80, ...-81, ...-82, ...-93, 20.21-01 Series Universa Doub e Sheet Meta Monitor
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2/29 BDK GB 5.17 KLASCHKA
In connection with these messages the press contro er a -
ows an individua eva uation via three potentia -free re ay
outputs K0 ... K2.
The current status of operation can be taken from the actua
signa behaviour. The detai s of the signa behaviour are de-
scribed from page 9.
Parameters and simi ar are entered using the four keys and
their possib e combinations (detai ed description under pos.
5).
Devices with a fie dbus interface, for examp e Profinet,
transmit via this interface instead of the re ay outputs the
measured va ue, the 0-, 1- and 2-sheet meta messages, the
memory ocation number of the current program and the cur-
rent thresho d va ue.
The se ection of the measuring program and initiation of the
measurement can take p ace via either a para e PLC inter-
face or the fie dbus interface.
When being operated without PLC (stand-a one operation),
the measurement program can be se ected on the device it-
se f and the measuring operation can be initiated by a prox-
imity switch inside the sensor.
. Versions
.1. Single Surface Contact Measurement
For sing e surface contact measurement, the DSP Sheet
Meta Thickness Sensor can be used for monitoring ferrous
sheets with thicknesses ranging from 0.2 to 5.5 mm. The
BDWF sensor is suitab e for non-ferrous sheets from 0.2 to
5.5 mm thickness.
With the DSPW sensor ferrous sheets in the range of 0.2 and
4 mm and non-ferrous sheets between 0.2 and 3 mm can be
monitored.
The DSP Sheet Meta Thickness Sensors for ferrous work-
pieces have an exciter coi which generates a strong mag-
netic fie d. The workpiece is temporari y pu ed onto the sen-
sor head and brought to magnetic saturation by the high f ux
density. A sensor coi measures the saturation f ux density,
which is approximate y proportiona to the thickness.
In the BDWF Sheet Meta Thickness Sensor for non-ferrous
workpieces, an exciter coi induces an eddy current in the
non-ferrous workpiece to be measured. The sensor coi
measures the fie d caused by the eddy current, which is ap-
proximate y proportiona to the thickness. Since the work-
piece is not pu ed onto the sensor head, no essentia air gap
between workpiece and sensor head is permissib e during
measurement. In both types of measurement, the accuracy is
about 0.1 mm at the ca ibration point or about 5 % of the end-
of-sca e va ue across the measurement range.
The DSPW Sheet Meta Sensor combines the two measuring
methods of DSP and BDWF.
Note:
On the disp ay, the indication of the sensor type
(DSPW/FE for ferrous, DSPW/NE for non-ferrous
sheets) a ows to se ect the materia being used.
A genera statement about the permissib e air gap for sing e
surface contact measurement is not possib e because it is
inf uenced by the thickness, the type of sheet meta , and the
sensor being used. Basica y, there shou d be no air gap, nei-
ther between the sensor and the workpiece nor between the
workpieces in the case of a doub e sheet. See diagrams in
the chapter “Sheet Meta Thickness Sensors”.
.2. Double Surface Non-contact Measurement
The doub e surface non-contact measurement is rea ised by
the Sheet Meta Thickness Sensors BDWD/S (transmitter)
and BDWD/E (receiver) for ferrous magnetic sheets with
thicknesses ranging from 0.2 to 3 mm and for non-ferrous
magnetic sheets with thicknesses ranging from 0.2 to 20 mm.
Note:
On the disp ay, the indication of the sensor type
(BDWD/FE for ferrous, BDWD/NE for non-ferrous
sheets) a ows to se ect the materia being used. Via
the parameterisation of the sensor connection in the
menu Parameter, the transmitter BDWD/S and re-
ceiver BDWD/E can be assigned to the according
connection (XS1 or XS2).
A transmitter coi in the (BDWD/S) transmitter generates an
a ternating magnetic fie d. A receiver coi in the (BDWD/E)
receiver measures the fie d, which is attenuated approxi-
mate y proportiona y to the thickness of the workpiece.
The accuracy is about 0.2 mm at the ca ibration point or
about 5 % of the end-of-sca e sensor va ue across the meas-
urement range. This measurement procedure is insensitive to
the re ative position workpiece – sensor heads and to air
gaps between workpieces, which may move during meas-
urement. Between sensor and sheet meta , however, a mini-
mum distance of 10 mm must be kept.
Strong sources of magnetic interference can inf uence the
measurement resu ts.
.3. Single Surface Non-contact Measurement
The DSD Sheet Meta Sensor is suitab e for monitoring
pieces of ferromagnetic sheet meta (other materia s on re-
quest) with a thickness range from 0.5 to 12 mm. The work-
pieces, however, must be p aced on a so id reference p ate,
for examp e, a conveyor be t.
The distance between the sensor and workpiece is detected
by the DSD sensor. Since the distance between the sensor
and the supporting p ate is fixed, the thickness of the work-
piece can be ca cu ated as the difference between the two
distances. The measured thickness can be compared with
the nomina va ue in order to detect the presence of a doub e
sheet.
The accuracy at the ca ibration point is 0.2 mm with DSD-18
and 0.5 mm with DSD-60 or 5 % of the end-of-sca e sensor
va ue across the entire measurement range.
Measurement can be taken as the meta sheet moves a ong
the sensor. With the sing e surface non-contact measure-
ment, an air gap between the workpieces and between the
workpiece and the supporting p ate can direct y inf uence the
measured thickness (The measured thickness wi appear to
be greater than the actua thickness).
