This is a new, old stock (NOS) Pepperl+fuchs WEM/Ex-DW-T Intrinsic Safety Barrier, also known as a Frequency Relay, Speed Monitor, or Tachometer Relay. It is designed for use in hazardous areas (Ex [EEx ia] IIC) to safely monitor frequency signals, such as rotational speed, from a Namur-type proximity sensor (din 19234). The unit provides a relay output (changeover contact) to interface with non-hazardous area equipment. It features a triple-digit display for frequency setting and dip-switches for function selection (overspeed/underspeed). It comes in its original Pepperl+fuchs box with documentation. Settings for the trip frequency (0 to 999 Hz) are clearly visible on the front face, which is also labeled with the part number 00369. The side-mounted dip-switches allow for precise configur.
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