Integrex Tool Eye Sensor: Wire Color to PCB Pad Mapping

Overview

The Mazak Integrex series multi-tasking machines use a fixed-mounted tool eye sensor inside the work envelope to detect tool length, tool presence, and (on some models) broken-tool conditions. The sensor is a 3-wire DC diffuse-reflective photoelectric switch, typically supplied by Omron as an E3Z-family diffuse-reflective head. On the Integrex, the sensor body is frequently potted or covered with an epoxy/clear-coat on the rear to resist coolant ingress, and the only serviceable entry point is the lead-wire side or, if the rear cover can be removed, the small SMD PCB that terminates the leads.

The failure mode discussed in the field — an operator pulling a stuck sensor and tearing the three lead wires off the small internal PCB pads — is one of the most common in-cell repairs on Integrex cells. The fix is straightforward once the wire-to-pad mapping is known, but the data is rarely printed on the housing and the OEM wiring diagram is not always shipped with the machine. This article consolidates the field-proven color convention, the PCB pad layout, the safe rework procedure, and the Mazak parameter re-set required after a sensor replacement.

Affected Hardware and Typical Part Numbers

While the Integrex platform accepts several Omron E3Z variants, the wire color scheme is consistent across the 3-wire DC versions:

Verify the exact variant by reading the laser-etched label on the sensor barrel before ordering a replacement. Cross-reference the Mazak spare-parts list with the Omron E3Z photoelectric sensor catalog or call Omron technical support with the serial plate data.

The Wire Color Convention

Two color sets appear in this repair, and both are correct — they are simply the external lead colors versus the internal PCB silkscreen:

If the silkscreen has worn off the PCB (common after coolant exposure), use a magnifier and look for the copper trace going to the power-input filter cap — the pad feeding the cap positive is V+ (red), and the pad on the ground side is V− (green). The remaining pad is the output (black).

Confirming NPN vs PNP Before Powering Up

The Integrex I/O cards are 24 VDC and are almost always sinking (NPN) inputs on the tool-measure probe circuit. Re-installing a PNP-output sensor in place of an NPN unit will produce a continuously-OFF input even with a tool in front of the eye, and can also back-feed voltage into the input card through the output stage. Verify the output topology with a multimeter before soldering the wires to the pads:

1. Apply 24 VDC between the brown (V+) and blue (V−) leads from a bench supply, current-limited to 50 mA.
2. Set the meter to diode/continuity. Place the red probe on V+ (brown) and the black probe on the output lead (black).
3. With no target in front of the sensor, an NPN output reads open (OL) and a PNP output reads ≈ 0.7 V (the body diode of the output FET).
4. Place a white card 50 mm in front of the lens. The reading should invert — NPN now reads ≈ 0.7 V, PNP now reads open.

If the sensor behaves as PNP and the machine is wired for NPN, swap for the correct variant rather than re-wiring. PNP-to-NPN adaptation with a pull-down resistor is possible but is not recommended in a coolant-rich cell because the added discrete components fail quickly.

Safe Removal Procedure to Prevent Pad Tearing

The pads on a sensor PCB are small SMD-style lands with through-hole plating for the lead wires. Pulling axially on the cable is the most common cause of pad lifting. To prevent a repeat failure:

1. De-energize first. Drop the e-stop and lock out the 24 VDC distribution breaker feeding the tool-eye circuit. The Integrex I/O backplane stays live even with the main spindle drive off.
2. Clean the area. Use coolant wand or chip wand to clear chips from the sensor pocket. Coolant in the lens produces false triggers during re-setup.
3. Loosen the mounting hardware (typically two M3 cap screws on a clamp block) before pulling. The sensor is a press-fit in a bored seat on most Integrex models; pulling while the clamp is engaged rips the pads.
4. Cut, do not pull. If the wires must be separated from the PCB, snip them 25 mm above the pad with flush cutters, then de-solder each stub individually. This preserves the pad land.
5. Document the orientation of the LED emitter window relative to the spindle axis with a marker on the body before removal. Re-installing rotated 180° will not damage anything but will require re-teaching the target offset.

Soldering the Leads Back to the Pads

Use a temperature-controlled iron at 320 °C with a 1.6 mm chisel tip and 0.5 mm lead-bearing solder (Sn60/Pb40 or Sn63/Pb37). Lead-free SAC305 is acceptable but requires 350 °C and shorter dwell time to avoid pad lift.

1. Strip 3 mm of insulation from each lead and pre-tin. Twist the strands tight before tinning to avoid stray whiskers.
2. Apply a small amount of no-clean flux (RMA type) to each pad.
3. Position the lead on the pad, heat the pad (not the wire) for 1.5–2 seconds, and feed a small amount of solder to the pad/wire interface.
4. Inspect each joint at 10× magnification. A good joint shows concave fillet wetting both the pad and the lead. A convex ball indicates cold joint — reheat.
5. Strain-relieve the cable. Apply a single bead of silicone RTV (Dow Corning 732 or equivalent) over the three joints, then clamp the cable 30 mm back from the PCB with the existing cable tie on the sensor body.

Re-Installation and Mechanical Alignment

1. Slide the sensor into its bore until the emitter window is flush with the front face of the mounting block.
2. Torque the M3 clamp screws to 0.6 N·m (5 in·lb). Overtightening cracks the plastic barrel.
3. Verify the cable exits downward (away from chip flow) and is routed in the existing P-clip on the table casting.
4. Re-apply power to the 24 VDC distribution and confirm the sensor LED illuminates.

Mazak Parameter Re-Set (Tool Eye Calibration)

After any tool-eye hardware disturbance, the Integrex controller must re-learn the tool-eye Z offset. The parameter paths differ by controller generation, but the underlying data is the same.

Procedure on a Mazatrol Matrix controller:

1. Jog the spindle to a known reference tool (a calibrated 50 mm steel block held in the spindle, for example).
2. From the TOOL EYE screen, select CALIBRATE. The controller will jog the spindle down toward the sensor and sample the trigger point.
3. Confirm the reading matches the reference within ±0.005 mm. If not, repeat with the spindle slowed to 10 % rapid (override dial on the operator panel).
4. Save the parameter set (PARAM → SAVE) and cycle power to commit non-volatile storage.

Verification Tests

1. Trigger test: Place a piece of white paper 50 mm in front of the sensor. The output LED on the sensor body should illuminate and the controller's tool-eye input bit should go active in the I/O diagnostic screen.
2. Re-trigger test: Remove the paper. The output should de-assert within 1 ms (E3Z standard response time).
3. Coolant soak test: Run a 5-minute wash-down program with the table flooded. The sensor must not false-trigger. If it does, the lens seal has been compromised and the sensor must be replaced rather than re-sealed.
4. Cycle test: Run a tool-length measurement macro (Mazatrol M-code TEM or G65 macro depending on post-processor) over 25 tool changes. Maximum repeatability spec on the Integrex is ±0.005 mm; values above this indicate the calibration was not saved or the cable is partially broken.

Troubleshooting Matrix

Preventive Recommendations

• Add the tool-eye sensor to the monthly preventive-maintenance checklist — wipe the lens with isopropyl alcohol and verify the cable strain relief is intact.
• Print the wire-to-pad diagram from this article and laminate it to the inside of the cell's electrical cabinet door so the next operator has the answer immediately.
• Stock one spare E3Z sensor variant (matched to the existing output topology) on the spare parts shelf. The Omron E3Z family is field-replaceable in under 15 minutes once the parameter is known.
• Train operators to never pull a stuck sensor axially. If chips have packed around the barrel, flood and brush first, then loosen the clamp screws, then extract.

FAQ