Sensor Parts
Components that tell the machine what is happening — detection, registration and position reporting. Most sensor faults are cleanliness or alignment; the sensor itself is the last suspect.
Component families
Typical Components
The exact configuration depends on your machine model. Your spare parts documentation — issued per machine — lists the qualified items for your serial number.
| Component | Role in the system | Condition to watch |
|---|---|---|
| Photocells / photoeyes | Detect product and film marks | Lens condition, contrast margin |
| Registration mark sensor | Reads the printed eye mark | Teach state at operating speed |
| Proximity sensors | Detect position without contact | Alignment, gap |
| Limit & home switches | Reference axis positions | Actuation point, fixation |
| Encoders | Report position and speed | Mounting fixation, cable integrity |
| Brackets & sensor cables | Hold and connect the sensors | Vibration looseness, flexing damage |
Condition & Replacement
Clean and re-teach before replacing.
- Sensor lenses are wiped daily — film dust and product residue cause most "sensor faults".
- Detection is re-taught whenever the product, film or format changes, at production speed.
- Intermittent faults often trace to cables and connectors in moving zones, not to the sensor.
Technical Note
Work through Sensor Alarms: Diagnosis and Registration Mark Detection Problems before ordering a replacement — the fix is usually cleaning, alignment or re-teaching.
Identifying a Sensor
Sensors look alike; functions differ.
- Machine model and serial number
- Part number on the sensor body, photographed
- What the sensor detects — product, film mark or position — and where it sits
See Before Requesting a Part for the full checklist.
Need help identifying a sensor?
Submit the request form with the machine details — identification comes before quotation.