microsonic dbk-4-CD-O-QP E+S Ultrasonic Double-Sheet Detection User Manual
- June 11, 2024
- microsonic
Table of Contents
microsonic dbk-4-CD-O-QP E+S Ultrasonic Double-Sheet Detection User Manual
Product Description
- No need for calibration to the sheet material or to the material weight (grammage)
- Grammages from 20 to 1,200 g/m2, films, thin sheet metals and fine corrugated can be scanned
- Can be mounted perpendicular to the passing sheet
- Special versions for use on sheeted printing presses and for paper gatherers
- Time to respond to double or missing sheets from just 0.5 ms
- Double-sheet and missing-sheet output
- pnp and npn versions available
Operating principle
The purpose of the double-sheet detector is to detect two or more sheets that are lying one on top of the other. The sensor system consists of a transmitter and a receiver with integrated evaluation electronics. An ultrahigh-frequency ultrasonic transmitter fires a sonic beam at the underside of the sheet. The beam causes the sheet to vibrate, which in turn causes a very small sound wave on the other side of the sheet. This sound wave is then evaluated by the ultrasonic receiver opposite. If there are two sheets one on top of the other (,,double sheet”), then the signal is weakened to such an extent that it hardly reaches the receiver.
The ultrasonic double-sheet detector is equipped with a control input that,
depending on the particular model, is used to select different response times
or to activate and deactivate the detector.
The detector has two operating modes:
-
Free Run-Mode
The ultrasonic double-sheet detector operates continuously. In the event of a double sheet or missing sheet, the corresponding output is set following the response time. When the error is cleared, the output is reset after the tripping delay. -
Trigger-Mode The ultrasonic double-sheet detector can be activated and deactivated by means of the control input. The control input is either leveltriggered or edge-triggered depending on the model of the detector. The response time in the event of a double or missing sheet is shortest immediately after activation, typically 0.5 ms. The control states in effect at the moment of deactivation are frozen until the next activation.
Important information for installation and application
When installing, starting up or carrying out maintenance work on the detection
system, always perform all measures essential to ensuring the safety of staff
and the system (cf. the instruction manual for the entire system and the
instructions of the system operator). The double-sheet detectors of the dbk
series have been designed for industrial applications. The sensors are not
items of safety equipment and must not be used for the purposes of personnel
safety and machine protection.!
Installation
Install the transmitter and receiver facing each other 40 ± 3 mm apart (see Fig. 2). Installation of the dbk is not dependent on the position.
Note!
-
The distance between the transmitter/receiver and the passing sheet must never be less than 7 mm.
-
The axiality must be 0.5 mm.
-
Angular deviation between the transmitter and the receiver must be no more than 2°.
-
When working with papers and thin films, we recommend you install the dbk perpendicular to the sheet (Fig. 3a).
-
When working with thin sheet metals, thicker plastic films (e.g. credit cards), install the dbk with a deviation of 27° from the perpendicular (Fig. 3b).
-
Types of paper that lead to false triggering when the dbk is mounted perpendicular (as a rule, types with air pockets) can frequently be scanned more accurately when the dbk is installed at an angle of 45° to the sheet. If the dbk is angled towards the corrugations of corrugated, the system can even be used to scan fine corrugateds (G and F; see Fig. 3c).
-
The maximum tightening torque for the nuts is 15 Nm.
-
If you install the transmitter in a recessed position or position a sheet guide between the transmitter and receiver, the hole must have a minimum diameter of 12 mm, but we recommend a diameter of 18 mm (Fig. 3). Î Connect the transmitter to the receiver using the 2-pin plug-in connector.
Note! -
The cable between the transmitter and receiver must not be connected to an external voltage.
-
Connect the 4-core or 5-core control cable of the receiver as shown in Fig. 4.
Start-up
Switch on the power supply of the dbk. Check that the system is functioning properly with the aid of a test sheet. Î Hold a test sheet inside the working range between the transmitter and receiver. The LED must light up green. (If the LED lights up red, check the installation dimensions of the dbk and the test sheet you have chosen). Î Hold a double test sheet (two sheets) inside the working range between the transmitter and receiver. The LED must light up red. Î Remove all sheets from between the transmitter and the receiver. The LED must flash red (green for dbk-4/ CDD O/QP E+S/POD).
Note The test sheet may be either a high grammage sheet of the material to be scanned or the test sheet available as an accessory from microsonic, which can be ordered under the article designation ,,dbk test sheet”. This test sheet serves as threshold material at room temperature and can be used to verify correct adjustment and operation of the dbk.
Installation hints and terminal assignments
Time diagrams
Dimensions
Technical data
microsonic GmbH / Phoenixseestraße 7 / 44263 Dortmund / Germany / T +49 231 975151-0 / F +49 231 975151-51 / E info@microsonic.de / W microsonic.de The content of this document is subject to technical changes. Specifications in this document are presented in a descriptive way only. They do not warrant any product features.