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Position Measurement — Analog Output — SCU5

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Not sure which size? Pick the sensor wide enough for your max expected wander + 10% margin. View all ODC Family models

Select your sensor model above to unlock datasheets, 3D models, support files, and your exact ordering list for this guide.

✓ What You'll Achieve

After completing this guide, wired to your SCU5 D+ controller with position output as a voltage or current signal for your PLC, drive, or display.

Estimated time: ~1–2 hours

This guide covers 3 measurement types — same sensor, different configuration:

Edge Position

Tracks one physical edge (left or right) of the web.

Centerline Position

Tracks the midpoint between both edges — absorbs width variation. In center mode the sensor sees both edges, so the web appears as a white rectangle on the controller display with black regions on both the left and the right.

Contrast/Line Position

Tracks a printed line, coating edge, or color boundary on the web surface.

☐ What You Need

SCU5 Analog

Which controller variant? The SCU5 D+ provides analog output only. If you also need Ethernet, use the SCU5 C(x)D+ (provides both).

Prerequisites

Sensor size selection: Choose sensor wide enough for maximum expected wander + 10% safety factor. For centerline, sensor must be wider than the web. For contrast/line, sensor only needs to see the tracked feature.

SCU5 Output Options

The "+" is the analog-output option — it adds a live analog signal of the position value on top of the model's base capability.

ModelOutputs
SCU5 D+Analog output of the live position value (voltage or current)
SCU5 C(x)D+Analog position value, plus Industrial Ethernet position data

1 Install the Sensor

Mounting differs based on measurement type.

Edge & Centerline

  • Mount in free span between two rollers (web unsupported)
  • Web edge must be at least 10 mm from the edge of the sensor sensing range
  • Mount closer to one roller to minimize web flutter
  • Web plane must be parallel to sensor length axis
  • For centerline: sensor must see both edges (or use dual sensors for wide webs)
Light source:
Edge: Infrared (IR) — default for edge and centerline on most materials
Contrast: White light — for visible color contrast. UV for fluorescent marks only.

Reference Documents

2 Wire the System

Sensor to SCU5, then analog output to your system.

  1. Sensor: Connect Quick Disconnect Sensor Cable (U2-01975) from ODC sensor to SCU5 port S1
  2. Power: Connect 24 V DC Input Power Cable (21218-5m) to SCU5 port P1
  3. Analog: Connect Analog Output Cable (U2515-71) from SCU5 Port 2 to your PLC/drive/display
Caution: The analog output is isolated. Do NOT connect these pins to 24 VDC power — the voltage and current signals are generated by the controller.

3 Configure & Verify

All three measurement types use the same sensor hardware. The type is selected in the controller configuration.

Edge Position

Tracks one physical edge (left or right) of the web.

  1. Connect sensor and power on — edge position appears immediately
  2. Set the sensor's electronic orientation (left or right) to match its physical orientation with respect to the web. When set correctly, the web appears as a white rectangle on the controller display with one black region: the left region is black when tracking the left edge, the right region when tracking the right edge.
  3. For analog: select edge type (left/right/center/width) and output range
  4. For Ethernet: position is immediately available in registers
What success looks like: The Web Detect Indicator — the green square at the bottom-left of the SCU5 or SCU6x display — turns green (it lights when the controller sees a valid edge or a valid taught contrast); quality factor > 10; stable position value tracking web movement.

Common Configuration Mistakes

  • No backup roller — web flutter corrupts pattern matching
  • Teaching on the wrong feature
  • Tolerance too tight (intermittent loss) or too loose (false matches)
  • Ambient light interference
  • Forgetting to re-teach after material change

View full configuration documentation

Troubleshooting
SymptomLikely CauseFix
The web position bar on the SCU5 display is completely white (single-sensor setup). The sensor's electronic orientation does not match its physical orientation with respect to the web. Change the sensor's electronic orientation (left → right or vice versa) so it matches the sensor's physical orientation with respect to the web. Set correctly, the web shows as a white rectangle with the left region black when tracking the left edge, or the right region black when tracking the right edge.
The web position bar on the SCU5 display is completely white (dual-sensor setup). One or both sensors' electronic orientation does not match their physical orientation with respect to the web. Configure each sensor so its electronic orientation matches its physical orientation with respect to the web — one sensor tracking the left edge, the other the right.

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