Kaman’s improved ThreadCheckerTM consists of a single electronics module compatible with any probe/material combination. Designed specifically for in-die use, it provides rugged, reliable verification of thread presence or absence in nearly any electrically conductive material. With Kaman’s proven eddy current technology at its core, threads can be checked regardless of part cleanliness, reducing the cost of implementation.

As an eddy current sensor, the system (probe plus electronics) detects the distance between the probe OD and the ID of the hole. In untapped holes, this indicates tap drill diameter. In tapped holes, this indicates pitch diameter of the threads.

The most popular implementation is to use the switched output wired to a PLC or other controller, programmed to alarm when no thread is detected. This alarm may stop the operation or may divert untapped parts from further processing. Alternatively, the analog voltage may be monitored. In this case, the user would program the PLC or other control device with whatever limits are suitable for the application.

Features include:

  • Universal electronics for any probe/material combination
  • Four internal probes from 4mm to 10mm
  • Two external probes: 6mm and 8mm
  • DIN rail mounting option
  • CE compliant
  • IP-67 rated probes and electronics
  • PUR jacketed probe and I/O cables
  • Go/no-go LED indicator
  • Push button teach
  • Both switched and analog outputs


Kaman Sensors