Failsafe position measurement with digital interfaces

Safety through redundancy

Wherever additional safety is required in an application or machine availability and technical function security need to be significantly increased, redundant systems offer significant advantages. This applies as well to the BTL7 multiple redundant magnetostrictive linear position sensors from Balluff. These are available with the two digital interfaces SSI and start/top.

The sensors in the rugged aluminum housing with IP67 protection are freely configurable and work completely without contact. With their up to three independent measuring tracks they meet the highest requirements for safety and availability. Compared with analog versions they are also less noise susceptible.

Ideal applications include wherever position information needs to be obtained directly in the pressurized area of hydraulic cylinders at pressures up to 600 bar and enhanced safety is required. This includes hydraulic drive technology, such as actuators in power plants, tilt sensing in rail vehicles or controlling casting ladle movements in a continuous casting plant.

With four different mechanical form factors and measuring ranges between 25 and 7620 mm they cover a wide range of application requirements. The measuring systems offer high resolution along with repeat accuracy of ≤ 0.5 µm with a measuring frequency of max. 1000 Hz. This makes them ideal for high dynamic applications in harsh environments. Thanks to their compact dimensions these systems can also easily replace already installed, non-redundant distance measuring systems. Often there are not even any modifications necessary to the actuators and fixtures.

Thanks to standard flanges (3/4 16UNF, M18 x 1.5, M30 x 1.5) or 6-hole flange mounting there are no surprises when installing. The sensor can be installed in the hydraulic area of a cylinder just as easily as the standard versions. Startup is convenient and practical: a software tool is used to easily set the output signal and even the most complex parameter settings. In practical operation diagnostic LEDs indicate the active channels so that defective channels can be detected directly on the unit. The non-contact measuring principle ensures high efficiency, extremely long service intervals and minimum downtimes, which today is a must in safety related areas.