Delay-Line label position timer
The XIAC Delay-Line is a specialist timing module developed for labelling machines where accurate label placement cannot be achieved reliably using standard PLC ON-delay timers.
Instead of producing a single delayed output, the Delay-Line replays the complete sensor signal after a precisely adjustable time offset. Pulse width, spacing, and event order are preserved — even when containers run close together or sensors produce multiple transitions.
The result is deterministic label positioning without mechanical rework, PLC reprogramming, or scan-time limitations.
PLC timers trigger once and collapse multiple sensor events into a single output. The Delay-Line preserves every event — exactly as it occurred — and shifts it in time.
What the Delay-Line actually does
In many labelling machines, the product sensor cannot be placed directly at the label peel point. A fixed time offset is therefore required between detection and label dispense.
Conventional ON-delay timers work only when products are widely spaced and sensor signals are clean. At higher speeds or with reflective containers, mislabels quickly appear.
Oscilloscope capture showing the Delay-Line in delayed pass-through mode. The lower trace reproduces the complete sensor signal exactly 2 seconds after the input — preserving pulse width and spacing instead of collapsing events into a single output.
Typical application
The Delay-Line is installed electrically between a product sensor (e.g. fork or photoelectric sensor) and the PLC input of a labelling machine. The PLC continues to operate normally, but receives a time-shifted version of the sensor signal that is aligned with the label peel position.
Where the idea came from
The concept behind the Delay-Line did not originate in industrial automation. Delay lines have long been used in other fields — such as colour television systems, audio processing, and laboratory instrumentation — to realign signals in time without altering their structure.
In those domains, the signal itself is already correct; it is simply early or late relative to another process. The solution is not additional logic, but a controlled shift in time.
When confronted with persistent label positioning problems that could not be solved reliably using PLC ON-delay timers, the same principle was applied to the sensor-to-PLC interface. The result is a delay-line designed specifically for industrial sensors — preserving event integrity while relocating it in time.
Other suitable applications
While the Delay-Line was developed specifically for labelling machines, the same delayed pass-through behaviour can be useful wherever a sensor event must be shifted in time without losing its structure.
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Conveyor-based reject or divert systems
Delay air jets or diverter gates while preserving closely spaced product events. -
Inspection or vision trigger alignment
Time-shift camera or inspection triggers without PLC scan-time jitter. -
Legacy PLC retrofits
Add precise timing behaviour to older PLCs without modifying validated logic. -
Sensor repositioning constraints
Compensate for mechanical mounting limitations where sensors cannot be placed at the ideal physical location.
In all cases, the Delay-Line preserves event timing and spacing instead of collapsing multiple detections into a single delayed output.
Key features
- Adjustable delay (standard): 0.000 – 2.000 seconds (1 ms resolution)
- True delayed pass-through of sensor signal
- Leading or trailing edge detection (optional centre of bottle trigger)
- Invertible input and output (NO to NC or vv)
- NPN and PNP sensor compatible
- Light-ON and Dark-ON compatible
- 12 V and 24 V operation
- Push / pull output (NPN / PNP compatible) with thermal protection
- Non-volatile storage of delay setting (setting re-loads at power-up)
- DIN-rail mount
Video demonstration
The video below shows the Delay-Line timer operating on a production labelling machine, correcting label position by replaying the sensor signal after a fixed time offset.
Documentation
Installation and operation instructions are available as a PDF: