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Highly Configurable Electronic Vibration Switch

High Level of Functionality in a Compact Enclosure

IMI Sensors offers several switch products at various levels of functionality and price. At the top end of the switch range is the fully-loaded electronic switch (Model 685B) that provides multiple signal outputs and high levels of customization in one compact enclosure. With a frequency range of 2-1,000 Hz, it is ideal for a variety of industrial applications, including cooling tower condition monitoring, HVAC equipment predictive maintenance and protection of vibratory screens and feeders.

The switch offers multiple outputs to aid a technician in not only recognizing a potential vibration issue on critical machinery, but also in diagnosing and fixing the problem. These outputs include two relays for individual alert and alarm responses, a 4-20 mA overall vibration output for continuous vibration monitoring by PLC, DCS or SCADA system and an analog raw vibration signal output for fault diagnostics.

The electronic switch is highly-configurable so as to be tailored to specific industrial applications.

  • Choice of Accelerometer Type: All products in the 685B Series utilize a piezoelectric accelerometer. The accelerometer measures vibration in acceleration and then integrates the data into a velocity measurement. Either an internal, pellet-style accelerometer or external accelerometer can be used. Use of an internal accelerometer is ideal for applications where a single installation effort and location is preferred. Use of an external accelerometer is ideal for applications where the vibration is taking place in an area where mounting of the switch box is not possible. These applications include small and/or confined spaces, underwater/wet environments and higher temperature environments (150-325 °F/66-163 °C).
  • Choice of Measurement Range: In order to provide a measurement range that corresponds to the application's requirements, the electronic switch can be factory-set to one of the following five options: 0 to 1.5 ips peak velocity, 0 to 3.0 ips peak velocity, 0 to 5 g peak acceleration, 0 to 15 mils peak to peak displacement or 0 to 50 mils peak to peak displacement.
  • Choice of Power Supply: The switch can be factory-configured to operate on either 85-245 VAC or 24 VDC.
  • Choice of Relay Type: There are two relays available in each electronic switch, one for an alert and one for an alarm. The user can select whether both relays are electromechanical or solid state. If the electromechanical option is selected, both relays will be Form C, SPDT relays with a 10amp switching current (30VDC/240VAC) with an adjustable 0-45 second time delay. If the solid state option is selected, both relays have a 5amp switching current (230VAC) with an adjustable 0-45 second time delay.
  • Choice of Enclosure Type: Options are available for Canadian Standards Association (CSA) Class I, Division 2 approved enclosures and CSA Class I, Division 1 approved enclosures. There are also other enclosure options available including external pushbutton reset, external BNC jack and LCD readout display.
  • Choice of Connection Ports: The switch enclosure can be outfitted with cord grips or ½" NPT conduit hubs depending on application requirements.