The mounting of magnetic sensors

Hall sensors

  • Installation

    When installing a Hall sensor, make sure that the measured object (gear wheel) is within the maximum working distance. Furthermore, the sensor should be centricly aligned to the gear wheel. Observe the minimum wheel width to ensure sufficient signal reserves. Working distance and installation instructions refer to gear wheels with involute toothing (DIN 867).

     

    Rotating direction of multichannel sensors

    Two Hall semiconductor elements output two differentiated signals shifted by 90°per tooth and thus allow for picking up both rotating speed and direction of a gear wheel. A clockwise turning gear wheel will result in channel A being in lead to channel B.


    Adjustment

    To ensure proper two-channel output functionality, the Hall elements of multichannel Hall sensors must be arranged in alignment to the wheel’s tooth module. The sensor must be aligned to the teeth of the gear by aid of the coding keyway and under consideration of the gear module.

Magnetic proximity switches

  • Permanent magnet - Alloy

    The switching distance of a magnetic sensor relates to the magnet deployed. Not only size but also alloy of the permanent magnet play a decisive role. The higher the energy product of the magnetic alloy in kJm³, the stronger the magnetic field and hence the more extended the switching distance.


    Permanent magnet - Alignment

    By principle, magnetoresistive proximity switches are polarity neutral, i.e. the sensor will detect both north and southpole of the permanent magnet. It is recommended to always attach the permanent magnet with one pole in alignment to the sensor to ensure reliable detection.

     

    Permanent magnet - Mounting

    The way a permanent magnet is mounted plays a crucial role in the sensing distance. When attached to a non-ferromagnetic carrier, the influence on the assured sensing distance will be nearly not noticeable. However, a permanent magnet mounted unshielded on a ferromagnetic carrier will enhance the switching distance by up to 25%. Attached flush or shielded to a ferromagnetic carrier, the switching distance will be reduced by up to 40% (always related to the assured sensing distance). If the permanent magnet is to be screwed on, always use non-ferromagnetic screws (e.g. stainless steel).

Magnetic cylinder sensors

  • Mounting - Cylinders with slot

    Conventional cylinders provide standard T- or C-slots. The cylinder sensors are simply introduced in the slot and secured – either by using a grub screw or by a metal plate which will lock in the slot after having tightened the fastening screw.


    Mounting - Round cylinders or cylinders with tension rods

    Some commonly deployed round cylinders or cylinders with tension rods may not provide a slot for sensor mount. In this case, the C- or T-slot sensors will be attached using clamps or bolts.


    Mounting - Special slots

    C-slot sensors can also be mounted in T-slots by using the adaptor from an accessory kit. Adaptors for special slots such as dovetail are also available.

Angle measuring sensors

  • Permanent magnet

    When attaching the magnet make sure that its magnetization direction (north / south pole) is aligned in a parallel manner to the sensor’s sensing face. The carrier material to hold the magnet should be non-ferromagnetic (e.g. no steel), otherwise it will hamper the sensing distance.

     

    Working distance

    The magnet rotor or the permanent magnet must be attached within the specified working distance to the sensor. Observe the specifications in the data sheet for axial displacement.

     

    Zero signal

    For coarse zero signal tuning, align the keyways provided at sensor and magnet rotor (accessory) with each other. Finetuning will be performed electronically by the downstream control. Clockwise rotation of the permanent magnet will generate a rise in the output signal.