Weld-immune magnetic field sensor

Intelligent position feedback in challenging environments

Welding is a harsh environment: Flying sparks as well as metal and weld splatter can cause heat damage or stick to the sensors and cables and impair their functionality. High welding currents generate magnetic interference fields which can also affect the sensor function. Not so with the interference-immune BMF 415KW magnetic field sensor. This sensor features a 5mm T-slot and is especially designed for use in pneumatic cylinders as found in welding environments (AC and MFDC equipment). In robotic cells it monitors for example the clamping state (open, closed) of pneumatically actuated clamps.

The BMF 415KW is available with a TPE or silicon jacketed sensor cable. This is much more resistant to weld splatter and abrasion than traditional PVC or PUR cables. This means it contributes to overall high equipment uptime. The sensor is available with M8 or M12 plug or as a version with open cable end.

For even greater process security the sensor is able to detect magnetic fields and suppress them for a specified time. The interference suppression time (tDSD) is preset to 600 ms and can be set to between 50 ms and 1000 ms via IO-Link. Important for the user: during this time the output signal does not change. The output retains the state it was in before the interfering magnetic field was detected.

The noise-immune BMF 415KW provides not only the actual process data but also comprehensive diagnostic data over IO-Link. In addition to the switching signal you receive information about the device status, operating temperature or current ambient conditions. It also monitors the number of start cycles. When a freely selectable limit value is violated, it issues a warning. In addition internal runtime counter continuously monitors the operating hours over the entire life of the sensor, both since the last service and the last start-up. This makes it possible to plan for a possible needed replacement at the next service interval.

Functionality

BMF magnetic field sensors query the piston position of pneumatic actuators precisely and without contact and detect the permanent magnets attached to the piston rod through the non-magnetic cylinder wall. The sensors thus provide a reliable and bounceless switching response with generous function reserves with respect to faulty and double switchpoints.