SICK WTB12-3P2431

SICK WTB12-3P2431 is a background suppression diffuse-reflection photoelectric sensor from SICK’s W12-3 series, with order number 1041411.

1. Key Specifications

Operating principle: Diffuse-reflection with background suppression

Sensing distance: 20 mm ~ 350 mm (standard white card, 90% reflectivity)

Light source: Visible red light LED, wavelength 640 nm

Light spot: Ø 6 mm @ 200 mm

Supply voltage: 10 ~ 30 In DC

Output: PNP complementary output (light-on/dark-on configurable)

Max. load current: 100 mA

Ansprechzeit: ≤ 330 µs

Switching frequency: 1,500 Hz

Adjustment: 5-turn potentiometer (sensitivity)

Verbindung: M12 × 4-pin plug

Abmessungen: 15.6 × 48.5 × 42 mm

Gewicht: Ca. 120 g

Protection rating: IP66 / IP67 / IP69K

Umgebungstemperatur: -40 °C ~ +60 °C

2. Modellbedeutung

WTB: Diffuse-reflection photoelectric sensor (Background suppression)

12: W12 series

3: 3-wire system

P: PNP output

2431: Function/configuration code (background suppression, M12 plug, red light)

3. Similar Models in the Same Series (W12-3)

WTB12-3P2431: Background suppression, 350 mm, PNP (this model)

WTB12-3N2431: Background suppression, 350 mm, NPN

WTF12-3P2431: Foresight suppression, 350 mm

WSE12-3P2431: Through-beam type (emitter + receiver), 20 M

WL12-3P2431: Retro-reflective type, 7 M

4. Typische Anwendungen

Small parts / transparent object detection

Level monitoring (material / liquid)

High-precision positioning, false-trigger prevention

Verpackung, Elektronik, and logistics production lines

Core difference between SICK WTB12-3P2431 and WTB12-3P2430: only the output function differs. All other electrical, mechanical, and optical parameters are identical.

1. Key Parameter Comparison

2. Detailed Difference: Output Function

WTB12-3P2431 (4-Stift, complementary output)

4-wire output: 2 independent PNP signals (Q1 normally open + Q2 normally closed)

Stift 1 (BN): +V, Stift 2 (WH): Q1, Stift 3 (BU): Q2, Stift 4 (BK): 0V

Vorteil: One signal for control, one for monitoring/feedback, suitable for safety circuits and dual-signal systems

WTB12-3P2430 (4-Stift, single output)

3-wire active: Only 1 PNP normally open (Q); Stift 3 (BU) not connected / non-functional

Stift 1 (BN): +V, Stift 2 (WH): Q, Stift 3 (BU): NC, Stift 4 (BK): 0V

Positionierung: Legacy / simplified version, basic detection only, no complementary signal

3. Model Code Explanation (SICK W12 Series)

`WTB12-3P243X`

WTB: Diffuse-reflection + background suppression

12: W12 series

3: 3-wire system

P: PNP output

243X:

2: Red light

4: M12 4-pin

X: Output function

X=1 → Complementary output (31)

X=0 → Single output (30)

4. Auswahlhilfe

Wählen 31 (1041411):

Requires dual signal / redundancy / status feedback

New designs, standard projects, beste Kompatibilität

Wählen 30 (1041410):

Direct replacement for legacy equipment (original 30 Modell)

Only requires single switching signal, cost-saving and simplified wiring

Abschluss: WTB12-3P2431 is the upgraded/standard version of 30. The core difference is complementary output; all other specifications are fully interchangeable (only wiring differs).

Below is the complete parameter comparison table for three sensors from the SICK W12-3 series:

WTB12-3P2431 (PNP background suppression), WTB12-3N2431 (NPN background suppression), WTF12-3P2431 (PNP foreground suppression).

1. Key Parameter Comparison Table

2. Key Difference Analysis

2.1 WTB12-3P2431 vs WTB12-3N2431

Only difference: Output polarity

3P2431: PNP output (active high, load connected to negative)

3N2431: NPN output (active low, load connected to positive)

Identisch: Sensing distance, background suppression, optical / mechanical / electrical parameters

2.2 WTB12-3P2431 vs WTF12-3P2431

Core differences: Suppression logic + distance + light spot

Background Suppression (WTB): Ignores distant background, detects only nearby objects → ideal for anti-background interference

Foreground Suppression (WTF): Ignores nearby objects, detects only distant targets → ideal for thin/small/transparent objects, anti-close false triggering

Distance: WTB 350 mm / WTF 175 mm

Light spot: WTB Ø6 mm / WTF Ø2 mm (finer)

3. Auswahlhilfe

Choose WTB12-3P2431:

Standard PNP systems, requires background suppression, sensing distance ≤ 350 mm

Choose WTB12-3N2431:

NPN systems, other requirements same as above (direct replacement for 3P2431)

Choose WTF12-3P2431:

Detection of thin/small/transparent parts (z.B., films, labels, thin sheets)

Needs to ignore close-range interference, detect only distant targets

Sensing distance ≤ 175 mm, requires fine light spot

As of April 2026, reference prices for genuine original SICK W12-3 series (WTB/WTF) sensors are as follows:

1. Target Models (Latest Quotations)

2. Key Price Factors
3. Output type

NPN (3Nxxxx) is ¥30-50/pc more expensive than equivalent PNP (3Pxxxx)

2. Sensing principle

WTF (foreground suppression) > WTB (background suppression)

Price difference: ¥200-250/pc (more precise optical system in WTF)

3. Order quantity

1 pc: Retail price (higher)

≥10 pcs: Agent bulk price (8%-12% untere)

4. Lead time and channel

In stock: As above

Indent order (4-6 weeks): Further 3%-5% Rabatt

Counterfeit / refurbished: ¥800-1,000 (not recommended, no warranty, unreliable)

3. European & US Official Prices (Referenz, tax & freight excluded)

WTB12-3P2431: €194/pc (ca. ¥1,500)

WTF12-3P2431: €278/pc (ca. ¥2,150)

Domestic agent prices are 10%-15% lower than European official prices (better for bulk orders)

4. Auswahl & Purchasing Advice

Best value: WTB12-3P2431 (Universal-, economical, compatible with most PLCs)

NPN required: Choose WTB12-3N2431 (slightly more expensive but direct fit)

Thin/transparent/small objects: WTF12-3P2431 (more expensive but accurate, no false triggers)

5. Authentizität & Garantie

Genuine product: Made in Germany, SICK yellow packaging, laser-engraved model, serial number verifiable on official website