SEARCH COIL TYPE MDB-C FOR METAL DETECTORS

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Hubert Gibson
5 years ago
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1 DESRIPTION OF EQUIPMENT Metal detectors protects the consumer from damage to health, the final product against metal contamination and processing equipment against damage by undesirable metal pieces. The Sartorius search coil, type MDB-, in conjunction with a electronic unit of the MDB-E series, represents a fixed metal detector which detects metal contaminations in all non- or low-conductive materials. APPLIATION The range of application of the MDB- is almost universal - only a few industries are mentioned below. INDUSTRIES: hemicals Wood and timber Plastics Food Tobacco Building products (bricks and tiles) Peat MDB- SEARH OIL TO PROTET: Processing machines etc. All types of saws, chippers, particle-board presses etc. alenders, mills, cutters, rollers etc. Processing machines etc. utting machines etc. Kneading machines, mills etc. Mills, presses etc. SEARH OIL ASING All-welded steel casing with tunnel-shape aperture (hard PV) available in different dimensions (see table). Protection: IP 55 Painting: hrome yellow RAL 1007 SENSITIVITY The sensitivity of the metal detector meets the special requirements of many industries. Alloy steels and non-ferrous metals (copper, brass, aluminium, lead) can be detected as well as ferrous magnetic steels 1

2 MEASURING PRINIPLE The search coil produces a normally balanced alternating magnetic field; a metal piece passing it distorts this field. The distortion is amplified in the electronics and produces a detection signal. PRODUT EFFET The measuring principle implies that magnetic properties or electric conductivity may limit the maximum obtainable sensitivity. In such cases it is recommended to send us representative samples of the product for testing. SELETION OF SEARH OILS APERTURE WIDTH The aperture width (dimension E of the table) depends on the width of the conveyor belt (plus an allowance for lateral belt movement). APERTURE HEIGHT Sensitivity depends mainly on the aperture height that is determined by the max. product height + belt + clearance. hoose the minimum necessary height (only the top belt passes through the detector). For the range of aperture heights see dimension of the table. DESIGNATION OF TYPE Its contains the aperture width (= search width) and aperture height in cm. Example: MDB- 100 x 40 Aperture width (= search width) = 1000 mm Aperture height = 400 mm SHOK ABSORBERS To minimize the influence by conveyor vibrations and to insulate the search coil from the construction it is fitted with shock absorbers. The search coil is fixed to the conveyor frame or a separate support using these shock absorbers. entre distances see dimension D. 2

3 AMBIENT TEMPERATURE: PRODUT TEMPERATURE: SPEIAL VERSION For product temperature exceeding + 50 an air-cooled version is available. Air-cooling reduces the aperture height and width by 20 mm each (dimensions and E ). PRODUT SPEED: 5 cm/s... 5 m/s (other speeds on request) ELETRONIS ONTROL UNIT The search coil is connected to a electronic control unit of the MDB-E series (see respective data sheets). ABLE ONNETION The search coil terminals are connected with the matching terminal numbers of the electronic control unit. The terminals are accommodated in two terminal boxes of cast aluminium at the side of the search coil. ABLE Screened cable with solder able braiding, screening effect: %, see respective data sheets of the electronic control unit. LENGTH OF ABLE 100 m maximum between search coil and control unit. MOUNTING In order to achieve the optimum sensitivity the metal detector is mounted around the top part of the conveyor belt. For this purpose the belt must be cut and vulcanised/glued together making sure no metal is included in the joint after fitting the detector. Should the return belt pass through the search coil a larger aperture must be chosen. Note: This will reduce the sensitivity. The search coil can be installed around non-metallic chutes or troughs. are should be taken to ensure that the conveyor belt (chute, trough) and the product to be inspected, pass through the coil aperture without touching it. 3

4 DIMENSIONS Search coil MDB- 60 A E B W 8 B S 8 PG13,5 160 B S B W 80 D ,3 F W PG13,5 30 D 6,3 119 F S MDB-... x A MDB-... x Installation position: Horizontal E Installation position: Vertical MDB-... x 12, MDB-... x.. 30 MDB-... x MDB-... x ,3 F W / F S F W/ F S F W/ F S 14 F W/ F S 50 G W / G S G W / G S G W / G S 4

5 TABLE Dimensions in mm MDB--... x... E , , A D B W F W G W B S F S G S Possible versions 5

6 INFLUENES ON THE SEARH OIL FIELD Vibrating or moving metal parts like rollers, metal sheets, access boards, chain drives, electric motors or machines may not be in close proximity of the search coil because they could influence the sensitivity. Motor drives, especially variable-speed D drives and 3-phase drives used with frequency converters and associated power supply cables, are to be installed as far as possible from the search coil. See Installation instructions for search coils - BA-2000" METAL FREE ZONE The metal free zone (MZ) should always be as large as possible. The following is a rule of thumb for the minimum required metal free zone in direction of transport (MZ see installation suggestion): MZ = B + (aperture heights x 3) Installation suggestion: MZ 1,5 x B 1,5 x A metal free zone corresponding to the aperture heights () should also be observed all around the search coil. Exceptions are made for the detector mounting structure (but not the cross bracings within this construction) and a possible support stand. Where the metal free zone cannot be observed as a result of the space available on site, losses of sensitivity must be expected. 6

Demagnetizing. Clamping Chucks. Clamping Plates. Lifting Magnets. Holding Magnets. Demagnetizing. Units. Control Electronics. Non-Ferrous Separators

Demagnetizing. Clamping Chucks. Clamping Plates. Lifting Magnets. Holding Magnets. Demagnetizing. Units. Control Electronics. Non-Ferrous Separators Wagner Magnete GmbH & Co. KG Obere Straße 15 D-87751 Heimertingen Phone: +49 (0) 8335 980-0 Fax: +49 (0) 8335 980-270 www.wagner-magnete.de e-mail: info@wagner-magnete.de Technology Full of Attraction