Skip to main content


(812) 867-3496

Force Displacement Switch Tester

Norman Tool is an Exclusive Distributor for the Snaptron Sapphire Force Displacement Switch Tester

Norman Tool is excited to offer the Snaptron Sapphire force displacement switch tester, which was engineered for accurate and repeatable force displacement measurements on many types of switches. The Snaptron Sapphire tester uses an LCD touchscreen display to show measurement data. This unique force displacement tester works well with metal or plastic dome switches, membrane switches, keypads of all types, and many other switches.

The force test follows ASTM standard F2592. The tests possible with this unit includes trip force, return force, standing free height, displacement / travel, tactile ratio, tactile activation slope, switch resistance, as well as other ASTM measurements. This tester can also detect two separate electrical contacts, and it can test resistive touch screens as well. The Sapphire is an excellent stand-alone, table-top tester for anyone needing to test force displacement for switches.

Snaptron Sapphire Force Displacement Switch Tester

Some of the Features, Benefits, and Available Options of this Force Displacement Switch Tester include:

  • Curve data option that generates a report containing force versus position data.
  • Create a force displacement curve.
  • Specify pass/fail parameters.
  • Follows ASTM standard F2592.
  • Access reports via a computer network, or a flash drive.
  • Touchscreen display and easy operation.
  • Two resistance circuits can measure multiple electrical contacts.
  • Adjustable test head accepts diverse product heights (and neck spacers available).
  • Can log all ASTM values for tests.
  • Custom specs and testing platforms available.
  • Test stands available.
  • Calibration weights (NIST traceable) or full calibration kits available.
  • 20 lb load cell available (10 lb std).
  • Actuator tip kit available (in various sizes).
  • Optional 12 V or 24 V supply voltages available (5 V std).
  • Fully customizable tester (contact us for details).
Snaptron Sapphire Force Displacement Switch Tester closeup

Force Displacement Switch Testing - Notes & Instructions


  • Position the center of the sample to be tested with the test probe center. The test probe must be perpendicular to the sample.
  • The sample must be on a hard flat surface.
  • The sample should be clean and free of any debris.


  1. Test speed 0.050″ [1.27mm] per second.
  2. Precondition the sample with 10 actuations.
  3. On the 11th cycle, the gauge will collect sample characteristic results.

The Force Displacement Curve

The force and displacement values when converted to a graphic curve can be used to distinguish the differences in tactile switch performance. As shown on the diagram below, the “Y” axis is the force characteristics, and the “X” axis shows the displacement (travel). The curve on top represents the forward travel of the switch to the contact point, while the lower curve shows the return travel of the switch to the open position. A variety of force and displacement (travel) characteristics can be graphically displayed, depending on the type of data collected by the measurement device. See below for a definition of terms. This is provided for a visual reference only.

Force Displacement Switch Tester diagram
Example Force Displacement Curve

Definition of Terms Used in the Diagram

Force Terms:

  • Fmax: Maximum force measured prior to or including Fmin
  • Frmax: Maximum force measured during return cycle after achieving Frmin
  • Fmin: Minimum force seen between Fmax and the point at which the probe movement ceases
  • Frmin: Minimum force seen during return cycle before reaching Frmax
  • Fc: Contact force – the force at contact closure
  • Fb: Break force – the force at contact break

Displacement (travel) Terms:

  • Tfmax: Displacement at Fmax
  • Tfrmax: Displacement at Frmax
  • Tfmin: Displacement at Fmin
  • Tfrmin: Displacement at Frmin
  • Tc: Contact displacement – the displacement at contact closure
  • Tb: Break displacement – the displacement at contact break


  • Switch testing (make): The displacement measurement on the force displacement curve between contact force (Fc) and minimum force (Fmin)
  • Switch testing (break): The displacement measurement on the force displacement curve between contact break (Fb) and return force (Frmin)

Contact Norman Tool

Contact Norman Tool regarding any questions on this Force Displacement Switch Tester, and/or to purchase a unit. Norman Tool provides a variety of test equipment for switches, keypads, touchscreens, and other electronic equipment and assemblies.