MachPro Tool Setter Wiring and Testing

NO probing with NC overtravel

Scope

This document describes how to wire a PHM2P (P) probe to a CNC controller and how to configure two controller inputs:

• Probe trigger input (Normally Open output).

• Overtravel alarm input (Normally Closed output).

Definitions

• DC: Direct current.

• 0 VDC: Power return for the 24 VDC supply (also called DC common).

• NO (Normally Open): The contact is open in the normal state. It closes when the probe triggers.

• NC (Normally Closed): The contact is closed in the normal state. It opens during an overtravel alarm.

• Dry contact: A relay contact that does not supply voltage. The controller (or an external supply) provides the input voltage.

Safety

• Use only a 24 VDC supply.

• Do not use the probe output to switch a load.

• Limit input current through the contact to 10 mA recommended, 20 mA maximum (resistive load).

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Wiring

Wire functions

• RED: +24 VDC supply

• GRAY: 0 VDC return

• BROWN + ORANGE: Probe trigger output, dry contact, NO

• GREEN + BLUE: Overtravel alarm output, dry contact, NC

• Cable: Oil-resistant, 6-core

1) Connect probe power (24 VDC)

1. Connect RED to +24 VDC.

2. Connect GRAY to 0 VDC.

2) Connect the probe trigger (NO) to one controller input

The BROWN–ORANGE pair is a dry contact. It works like a switch.

Use one of these common methods:

Method A: Input turns ON when it receives +24 VDC

1. Connect +24 VDC to BROWN (or ORANGE).

2. Connect the other wire (ORANGE or BROWN) to the controller input terminal (example: PROBE_IN).

3. Wire the controller input common (COM) as the controller manual specifies.

Method B: Input turns ON when it is connected to 0 VDC

1. Connect the controller input terminal (example: PROBE_IN) to BROWN (or ORANGE).

2. Connect the other wire (ORANGE or BROWN) to 0 VDC.

3. Wire the controller input common (COM) as the controller manual specifies.

3) Connect the overtravel alarm (NC) to a second controller input

The GREEN–BLUE pair is a dry NC contact.

Wire it to an input so the normal state is a closed circuit. A broken wire must create an open circuit (failsafe).

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Test the I/O at the motion controller

Prerequisites

• Probe is wired and powered (24 VDC).

• You can view input status in the controller I/O monitor (or diagnostics page).

1) Verify power

1. Measure voltage from RED to GRAY.

2. Confirm the voltage is 24 VDC.

2) Test the probe trigger input (NO contact)

1. Open the controller I/O monitor.

2. Find the input that you wired as the probe input (example: PROBE_IN).

3. Confirm the normal state:

   • The probe input must show not active.

4. Manually trigger the probe.

5. Confirm the change of state:

   • The probe input must change to active while the probe is triggered.

6. Release the probe.

7. Confirm it returns to the normal state.

If the input state is reversed, do not change wiring here. Record the behavior for the software configuration step.

3) Test the overtravel alarm input (NC contact)

1. In the I/O monitor, find the overtravel input (example: OVERTRAVEL_IN).

2. Confirm the normal state:

   • The overtravel input must show active/healthy (closed circuit).

3. Create an open-circuit condition:

   • Trigger an overtravel event if your system allows a safe test, or

   • Temporarily disconnect one of the alarm wires (GREEN or BLUE) at the controller input.

4. Confirm the change of state:

   • The overtravel input must change to inactive/fault (open circuit).

5. Reconnect the wire (if removed).

6. Confirm it returns to the normal state.

4) Optional continuity checks (power OFF)

Use a multimeter in continuity mode:

• BROWN–ORANGE:

  • Open in normal state.

  • Closed when the probe is triggered.

• GREEN–BLUE:

  • Closed in normal state.

  • Open during overtravel.

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Reference specifications (selected)

• Output mode (probe): NO

• Trip (pre-travel): 5 mm

• Repeat accuracy: 0.001 mm at 50 to 200 mm/min

• Contact life: 3,000,000 operations

• Protective structure: IP67

• Contact force: 1.5 N (install vertically)

• Contact rating: 24 VDC, 20 mA maximum (recommended 10 mA, resistive load)

• Tool face diameter: 20 mm or 40 mm

• Installation hole distance: 40 mm

• Indicator: NC LED illuminates when operating

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MachLabs Terms and Conditions

The MachLabs Team
http://www.mach-labs.com
14518 County Road 7240, Newburg, MO 65550
support@machsupport.com 

As we are in active beta testing, please email your observations and questions. We sincerely appreciate your feedback!