Jemtech VSY-W high-sensitivity safety switch range

The VSY-W range of high sensitivity safety switches uses technology similar to RFID with a reader in the switch body and an active transponder tag in the switch key.

The device incorporates larger antenna coils in the switch and key, allowing for greater misalignment of the pair. In some applications, this misalignment is inherent, so this greater sensitivity is beneficial.

The coils allow sensing distances of more than 50 mm face to face at misalignments of more than 30 mm in any direction off-centre. Misalignments of up to 65 mm off-centre are tolerated at sensing distances of 30 mm or less.

The device can be used to detect safe positioning of overhead gantry cranes that use automated positioning, conveyor systems, trolley-position sensing and other applications where moving plant has wide tolerances in the safe parked positions.

The design uses polyurethane plastic outer housings and polyurethane rubber encapsulation. Available with cable tails or IP68-rated plugs as options, the devices can be used in hose-down, condensing and corrosive atmospheres. There are no cavities in the housing or moving parts to foul or jam.

The safety switches use dual-redundant microprocessor channels as well as dual receivers to ensure that failure of any part of the device can be detected at or before the next safety demand.