Positioning Systems

Rope encoders are mainly used for vertical axis applications on EMS and Floor Carrier Systems.
Horizontal positions employ different systems, for example:
Position Light Barriers, Transponder Reader, Rotary encoders and Barcode- or 2D-Scanner.
 
Rope Encoders

SLG 2000 and SLG 5000 are devices made by LJU years ago with a cost effective RS-485-interface when there were no specific encoders available. Today there are a couple of manufacturers offering plug-and-play devices which can be connected to LJU controllers without special configuration. Alternatively, LJU offers SSI/RS-485 interfaces or when using Safety Boxes on the carrier also SSI encoders are directly connected to the Safety-PLC. Rotary encoders with LJU-Bus or SSI-Interface are used for turning axis on special carriers or as redundant speed and position detectors.

Light Barriers and Position Scanner

Simple reflection based light barriers or double light barriers (e.g. DLS-2) are used since years in monorails to control assembly speed. Using a special algorithm it is possible to move with a standard asynchronous motor down to about 1 Hz rotor frequency in a stable operation mode for hours without using an external fan and without overheating the motor.

Accurate absolute position detection on the carrier is possible by PLA-14 and PLA-140 and a coded aluminium rail, both developed and delivered by LJU and in use in far more than 300 installations. Also using these kind of devices it is possible to perform slow motion assembly speed with standard asynchronous motors like described above. Accurate positioning as well as position dependent carrier activities require the use of these sensors.

Barcode-Scanner

The optical linear measurement sensor OLM-100-1001 is an optoelectronic sensor and is used for position reading / positioning using a barcode strip in industrial transport systems.

By appearance of bar code scanners on the market the share of the scanners is increasing and LJU also provides these devices or customers can use products of other manufacturers with already implemented LJU protocol. Also using these kind of devices it is possible to perform slow motion assembly speed with standard asynchronous motors like described above. Accurate positioning as well as position dependent carrier activities require the use of these sensors.

They are available with SSI interface and for standard applications with the more cost effective RS-485, connected directly into the internal controller architecture by standard M12-cable.

Transponder and Transponder Reader
Active as well as passive transponder are used to detect positions, to calibrate drives, to neutralize slipping wheels or to guarantee accurate positioning by using transponder readers on the carriers. They are used preferrably in floor transport systems. LJU Automatisierungstechnik offers own technology for special purposes as well as interfaces for devices of 3rd party manufacturers for use in carriers.
Further information can be found in our download area.
Do you require consultation on a project if so please contact your nearest LJU partner (see partners on our contact page) or use our contact form.