SICK 1043840 WLG4S-3F3234 PNP Glass Sensor

Technical Overview

The SICK WLG4S-3F3234 is a polarized retro-reflective photoelectric sensor for detecting transparent objects that attenuate the beam by more than 8%. Its coaxial optics work with a reflector and provide a specified 0–3 m sensing range with PL80A, with 0.01–5 m listed as the maximum range. A visible 650 nm PinPoint LED produces a typical 45 mm spot at 1.5 m for alignment. The PNP output uses dark switching, with response below 0.5 ms under resistive load and 1,000 Hz switching at a 1:1 light/dark ratio. One teach-in button and external teach-in on pin 2 supports sensitivity setup. The IP66/IP67 ABS housing has a PMMA screen and a 100 mm PVC cable with an M8 4-pin connector.

Polarized coaxial retro-reflective sensor, 0–3 m with PL80A, PNP dark switching, transparent-object teaching and 100 mm M8 4-pin cable.

Key Features

Polarized retro-reflective sensing with autocollimation/coaxial optics

0–3 m sensing range with PL80A reflector; maximum 0.01–5 m

650 nm red PinPoint LED; typical Ø45 mm spot at 1.5 m

Transparent-object detection at >8% beam attenuation; AutoAdapt available

PNP dark switching output, maximum ≤100 mA

<0.5 ms response with resistive load; 1,000 Hz at 1:1 light/dark ratio

One teach-in button and external teach-in on pin 2

M3 threaded mounting and received-light/power indicators

100 mm PVC cable with M8 4-pin connector; do not bend cable below 0 °C

10–30 V DC; 20 mA without load; IP66/IP67 ABS/PMMA housing

Technical Specification Matrix

Parameter	Value
Functional principle	Photoelectric retro-reflective sensing with autocollimation/coaxial optics; reflector required
Sensing range	0–3 m with PL80A reflector
Maximum sensing range	0.01–5 m with PL80A reflector
Polarization filter	Yes
Reflector minimum distance	Coaxial/autocollimation optics without reflector minimum distance; maximum-range specification retained separately
Light source	Visible red PinPoint LED
Wavelength	650 nm
Light spot size	Typically Ø45 mm at 1.5 m
LED service life	Average 100,000 h at ambient +25 °C
Digital output	PNP; maximum output current ≤100 mA
Switching mode	Dark switching
Adjustment	One teach-in button and external teach-in on pin 2
AutoAdapt	Yes
Attenuation along beam	>8%
Power supply	10–30 V DC
Residual ripple	<5 Vpp; remain within supply limits
Current consumption	20 mA without load
Protection class	III
Circuit protection	Supply reverse-polarity protection; interference suppression; output overcurrent and short-circuit protection
Housing design	Slim rectangular
Connection	100 mm PVC cable with M8 4-pin connector
Cable handling	Do not bend below 0 °C
Mounting	M3 threaded mounting holes
Indicators	Green power indicator; orange received-light indicator
Housing material	ABS plastic
Front screen	PMMA plastic
Cable material	PVC plastic
IP rating	IP66/IP67
Operating temperature	−40 to +60 °C
Storage temperature	−40 to +75 °C
UL file	NRKH.E181493 & NRKH7.E181493
MTTFD	1,215 years
DCavg	0%
Physical Weight (kg)	0.03
Mission time	20 years
Response time	<0.5 ms; signal transit with resistive load
Switching frequency	1,000 Hz at light/dark ratio 1:1
Cable conductor cross-section	0.14 mm²
Cable diameter	Ø3.4 mm
Pin assignment	1 BN=L+; 3 BU=M; 4 BK=Q; 2 WH=Teach input

Parameter

Value

Functional principle

Photoelectric retro-reflective sensing with autocollimation/coaxial optics; reflector required

Sensing range

0–3 m with PL80A reflector

Maximum sensing range

0.01–5 m with PL80A reflector

Polarization filter

Yes

Reflector minimum distance

Coaxial/autocollimation optics without reflector minimum distance; maximum-range specification retained separately

Light source

Visible red PinPoint LED

Wavelength

650 nm

Light spot size

Typically Ø45 mm at 1.5 m

LED service life

Average 100,000 h at ambient +25 °C

Digital output

PNP; maximum output current ≤100 mA

Switching mode

Dark switching

Adjustment

One teach-in button and external teach-in on pin 2

AutoAdapt

Yes

Attenuation along beam

>8%

Power supply

10–30 V DC

Residual ripple

<5 Vpp; remain within supply limits

Current consumption

20 mA without load

Protection class

III

Circuit protection

Supply reverse-polarity protection; interference suppression; output overcurrent and short-circuit protection

Housing design

Slim rectangular

Connection

100 mm PVC cable with M8 4-pin connector

Cable handling

Do not bend below 0 °C

Mounting

M3 threaded mounting holes

Indicators

Green power indicator; orange received-light indicator

Housing material

ABS plastic

Front screen

PMMA plastic

Cable material

PVC plastic

IP rating

IP66/IP67

Operating temperature

−40 to +60 °C

Storage temperature

−40 to +75 °C

UL file

NRKH.E181493 & NRKH7.E181493

MTTFD

1,215 years

DCavg

Physical Weight (kg)

0.03

Mission time

20 years

Response time

<0.5 ms; signal transit with resistive load

Switching frequency

1,000 Hz at light/dark ratio 1:1

Cable conductor cross-section

0.14 mm²

Cable diameter

Ø3.4 mm

Pin assignment

1 BN=L+; 3 BU=M; 4 BK=Q; 2 WH=Teach input

Industrial Applications

1. Counting transparent containers on a packaging conveyor

A packaging conveyor can align the sensor with a PL80A reflector across the container path. The sensor evaluates the reduced returned light as separated transparent containers cross the beam. External counting logic records the switching transitions. Actual wall material, container shape, attenuation, alignment and available gaps are validated within the 0–3 m sensing range.

Problem Solved

Beam-attenuation events provide external counting logic with a reference for separated transparent containers, helping track product flow where a transparent wall may transmit much of the emitted light.

Transparent containers PL80A reflector PNP transitions

2. Recognizing a break in a transparent material web

A material feeder can route a transparent web across the optical path between the sensor and reflector. The sensor distinguishes the attenuated web-present state from the unobstructed reflector return when a break opens the path. External line control evaluates the change against the expected material state, with actual film attenuation, flutter and the selected sensitivity validated during setup.

Problem Solved

A change from the taught material-present return to the clear reflector return identifies a possible web break, allowing external feeder control to respond before subsequent processing runs without material.

Web continuity Beam attenuation External line control

3. Identifying container accumulation at a transfer point

At a conveyor transfer, a transparent container that stays in the optical path can maintain an attenuated reflector return. External control evaluates how long the selected PNP state persists to distinguish a passing container from sustained occupancy. The actual container attenuation is validated above 8%, and the PL80A reflector is positioned within the specified sensing range.

Problem Solved

Sustained beam attenuation provides external conveyor control with an occupied-transfer indication, helping it coordinate upstream release when a container remains at the transfer instead of clearing normally.

Sustained occupancy External timing Container flow