Tormach 440 mill, economy probe interface
The economy probe does not equal or replace the Tormach high quality probe. With careful tuning the economy probe provides reliable error free results at a fraction of the price. I place my probe in a Tormach TTS collet for alignment and never remove it. Leadshine inputs are 12 volt sourced and provides ground pins for the inputs. The input ground pins are there for a reason use them not the machine ground. I chose a 12 volt power source to maintain compatibility with the Leadshine input / logic levels. The supply conveniently snaps on the machine DIN rails. At the time of this design the probe was only available in Normally Open (high when not triggered). The FET 2N7000 and resistor fits conveniently in the DIN connector shell. A little silicone adhesive provides insulation and mechanical stability. The 10 meg resistor on the FET gate is to prevent false trips when the prove is disconnected yet DIN connector is plugged in. The Setup - Probe Polarity / Active or Passive did not do as expected, it did not negate probe output from high to low. This was confirmed by Tormach tech support.
The Leadshine sources 12 volts to it’s input pin.
The Leadshine Input Ground pins appear to level shift related to machine ground.
The 2N7000 is an N-channel enhancement-mode MOSFET
Example: Probe is pulled high (not triggered) the FET inverts pulling Leadshine input low, probe status is distinguished.
Probe is triggered, signal low and FET inverts. The low probe signal biases the FET off and lets the Leadshine input go High illumination the status indicator.
Probe.pdf (38.8 KB)