Tuesday, December 31, 2013

Robertshaw Selection Guide for Vibration Switches

Industrial Vibration Switches from Robertshaw ~ Selection Guide

Robertshaw Vibration Instruments can be used on rotating or reciprocating machines. To select the proper instrument for your machine, follow the steps below.
  1. Select the unit that meets the environmental conditions that your machine is located in [hazardous area (explosion-proof or I.S.) or non-hazardous; temperature range].
  2. Select the power supply and/or remote reset voltage required.
  3. Select the unit that provides you with the required measurement type, range and frequency for your machine. The type would be acceleration (G's) or velocity (IPS). The range would be the G range or IPS range. The frequency would be in Hertz (RPM of machine ÷ 60).
  4. If you require time delays (Start, Monitor or Start & Monitor delays – see note below), select the instrument that offers that feature. Models 375A/376A series offer fixed time delays; Model 566 offers adjustable Monitor Delay; Model 563A MUST BE used with Vibraswitch Model 366 or 365, and provides adjustable time delay for the units that are connected to the 563A Monitor. If time delay is not required proceed to step 5 below.
  5. Select the function that you desire:
    1. Alarm or shut down only by:
      1. Electrical SPDT or DPDT Switch Operation (Models 365/366, Models 375A/376A with Start Delay Only).
      2. Solid State Triac Switch Operation (Models 375A/376A except for Start Delay ONLY Model which has SPDT Switch Contacts).
      3. Pneumatic Operation (Model 368).
    2. 4-20 mADC output only (Models 570B/571A).
    3. 4-20 mADC output with alarm and/or shut down contacts, triac outputs (Model 566).
  6. Check to see if the Model selected above has a mounting configuration suitable for your application. All units are surface mount except for the following:
    1. Models 570B/571A are stud mount.
    2. Model 563A Monitor is used with the surface mount 365/366 Vibraswitches to provide adjustable start and monitor time delays.
  7. After you have made your selection, review the complete Product Specification Sheet to verify your selection is correct.

    Start, Monitor, or Start & Monitor Delays are used to prevent unwanted shut down or alarm during start-up or normal operation of your machine.
    1. Start Delay: Prevents unwanted shut down when excessive vibration exists (which exceeds the set-point of the vibration switch or monitor) during the start-up of the machine.
    2. Monitor Delay: Prevents unwanted shut down when short excessive vibration spikes occur (which exceed the set-point of the vibration switch or monitor) during normal operation of the machine. Spikes are typically caused by detonation, cavitation, other machinery in the immediate area, etc.

Sords Electric Sells Robertshaw Vibration Switches