For precise position display, a range of digital position indicators are available for use with ActionJac™ Worm Gear Screw Jacks. These indicators measure the rotation of the input shaft and display a corresponding position in a counter window. The display value per input shaft revolution is variable and is achieved through a series of gear reductions configured to accommodate different jack ratios, lift shaft leads and travel distances. Contact Nook Industries to determine actual readout scaling available for your application. Not for use with motorized applications. Long strokes may result in counter "rolling over."


  • Determine Mounting Position
  • Count Increase or Decreases with Extension of Shaft


Please see (See Image 2 in Figure 1 Below) for example and example of counter designations.

CAUTION: Consult Nook Engineering when adding a counter. Some jack configurations may have limited travel.

Please see (See Image 3 in Figure 1 Below) for detailed product codes and diagrams.

Product Code Increase or Decrease with extension of travel Shaft Extension
CEI Increase without shaft extension
CED Decrease without shaft extension
CTI Increase with worm shaft extension
CTD Decrease with worm shaft extension
CAI Increase with 4" handwheel*
CAD Decrease with 4' handwheel*
CBI Increase with 6" handwheel*
CBD Decrease with 6" handwheel*
CCI Increase with 8" handwheel*
CCD Decrease with 8" handwheel*
CDI Increase with 10" handwheel*
CDD Decrease with 10" handwheel*

* See handwheel page 185 to select the correct size for jack model.

Counter Positions

Please see (See Image 4 in Figure 1 Below)

Figure 1