The Valvis from IFM Efector Inc., Exton, PA, installs on the top of a linear single- or double-seat valve and reliably detects stroke position up to 80 mm. The sensor incorporates 16 individual air coils positioned closely together to create a linear inductive sensing field. Each coil is connected to the microprocessor-controlled electronics. As a valve stem enters the sensing field, coils detect the valve stem at a resolution of 0.2 mm and compares the resulting signal to the teach-in switch points. Available in a 3-wire Micro DC analog output version and a 5-wire Micro DC version with 3 switching outputs, the sensor can monitor seal wear and seal parameters and send an alarm signal to a PLC when it detects changes in condition.
ifm efector inc.