Roland Electronic has added the system I100-S-WI to the low-cost series R100. It is especially well suited for the metal packaging industry because of its capability to measure tinplate and aluminum single-sidedly. In addition, it is also capable to measure  nonmagnetic stainless steel up to 3 mm sheet thickness.
           
The system consists of the sensor, cable and the control unit. In general, the sensor is placed onto the sheet for measurement purposes. Having M42 thread it can also be mounted into Roland vacuum cups. For the use in sheet feeding the sensor is mounted flush or recessed into sheet feed tables with the maximum air gap between sensor and material not exceeding 2 mm and remaining constant.

The measurement is based on the induction principle where one sheet in front of the sensor dampens the electromagnetic field. An additional sheet - double sheet - results in additional damping. The dampening of the receiver signal is analyzed, displayed and also issued as a 0 - 1 - 2 switching signal.

The system has been optimized for easy set-up and operation. An external switch signal or PLC input can be used to select the type of material: tinplate, non-magnetic stainless steel or aluminum. Teach-In is accomplished with push button or an external switch signal. This generates the lower and upper switching thresholds symmetrical to the receiver voltage for one sheet. The relative switching thresholds are factory adjusted. However, they can be individually adjusted and stay in memory in case of power outage. Power supply is 24 VDC.

Material Type and Thickness:

Material / Sheet Thickness / Max. Sensor Gap
       
Tinplate / 0.15 ...0.5 mm  / 2 mm
Aluminum / 0.05 ...0.4 mm / 2 mm
Non-magnetic stainless steel / 0.50... 3.0 mm / 2 mm