Access guards for machines and systems are often complex systems with different individual components, which must be individually assembled and compatible. This also requires long installation and start-up processes. Markus Pollmeier of BEUMER, where the MLDSETs are used in palleting and packaging systems, explains: "Leuze electronic has developed MLDSET protective sensor sets, which are easy to install via Plug and Play with or without the muting function.
"The special thing about the MLDSET systems from Leuze electronic is that all of the access guarding components are pre-mounted for typical muting applications in a practical way. This saves a lot of time during installation as well as during start-up on site."
He sees another advantage in that fact that ready-made systems can also be installed easily by technicians that have not been specially trained, worldwide. After all, the BEUMER group is a company that operates all over the world.
The BEUMER Group is a manufacturer of intralogistics in the areas of conveyor and loading technology, palleting and packaging technology, and also sorting and distribution systems. Together with Crisplant a/s and Enexco Teknologies India Limited, the company group has around 4000 employees in numerous branches and is present in over 70 countries worldwide. Typical systems in which the safety photoelectric sensor sets from Leuze electronic are used are high palletisers such as the BEUMER paletpac system, palletising robots in the BEUMER robotpac series and packaging systems such as the BEUMER stretch hood.
Those systems are individually customised to the respective requirements, and take the product properties of the individual packaged goods into consideration as well as the desired packaging patterns and pallet sizes. Normally, these systems are completely enclosed in safety barriers. In "˜gaps' and open locations, particularly for moving materials in and out, MLDSET systems are used with light scanners as muting sensors for unimpeded material transport.
Pollmeier explains: "As standard, muting is triggered in situations where packages or pallets are continuously fed in by the conveyor system using muting sensors, i.e. additional photoelectric sensors. Feeding or delivery stations at which pallets are put in or taken away by forklift trucks can also be equipped with induction loops instead." In areas in which the system is used for access protection only, MLDSET is used without muting.
In any case, the systems are always delivered to suit the application. This includes defined cable lengths, connectors and cable routes and also a special acknowledgment unit with an illuminated start button or input and output signals that have been adapted for the BEUMER control concept.
The core component of MLDSET is the MLD 500 multiple light beam safety device with transceiver design. Systems such as this consist of an active transceiver (transmitter and receiver together in one housing) and a passive deflecting mirror without an electrical connection. Pollmeier stresses: "The transceivers are normally twin-beam and have an integrated muting indicator. Leuze electronic also offers triple-beam systems as a special feature."
According to Pollmeier, another advantage of MLD devices is that they are generally suitable for low-temperature environments and are fully functional up to -30degC. For BEUMER, this is an important product characteristic because conveyor, palletising and packaging systems are frequently used in open, drafty halls.
The MLD 500 multiple light beam safety devices are already pre-mounted in device columns with appropriate lengths. The set includes a complete mounting kit for exact base adjustment. Special spring elements provide an independent reset after mechanical impacts.
In special cases, the MLDSET includes series 25B muting light scanners as well as the MLD 500. For quick and easy installation, these muting sensors are already pre-adjusted in mounting arms, so-called muting sensor sets. These arms are mounted on the side of the UDC device columns, where the muting sensors are easy to adjust. Pollmeier summarises: "With these muting sensor sets, we no longer need to think about the arrangement of the muting sensors."
With the Multiple Light Beam Safety Devices in the MLD 500 series, a total of six different muting operating modes can easily be implemented for a wide variety of applications. Configuration is carried out using wiring or pin assignments - other aids such as a PC, software, etc., are no longer necessary. In addition to partial muting, MLD 500 safety sensors make timing controlled 2-sensor muting (T-Shape design) and sequence controlled 2-sensor muting (L-Shape design) possible. In addition, systems for timing controlled 4-sensor-muting can also be created with the modular system sets.
L-shape designs are used in situations where pallets exit danger zones, particularly if little space is available outside of the danger zone. With T-Shape designs the transport material can be moved in both directions through the protective field. Timing controlled 4-sensor muting is used when the muting sensor light beams should not cross due to a special application situation but must be parallel instead, for example with reflective materials or under disruptive environmental conditions.
For more information about access guarding with MLDSET please visit www.leuze.co.uk.