Pepperl+Fuchs RLK28-55-Z_31_116 Retroreflective Sensor

Technical Overview

The Pepperl+Fuchs RLK28-55-Z/31/116 is a versatile retroreflective photoelectric sensor designed for reliable object detection in diverse industrial automation applications. It operates using modulated visible red light and features programmable time functions. Housed in a robust ABS plastic enclosure, it offers a wide operating voltage range and a robust relay output for flexible control and enhanced safety in harsh industrial environments.

Key Features

Universal series with highly versatile fields of use.
Resistant against noise for reliable operation under all conditions.
Programmable time functions: GAN (ON delay), GAB (OFF delay), IAB (one-shot), as well as GAN-GAB and GAN-IAB as double functions.
Uses modulated visible red light as its light source.
Features a robust relay output with 1 alternator (SPDT).
Constructed with a robust ABS plastic housing.
IP67 protection rating ensures durability in harsh industrial environments.
Wide operating voltage range from 12 to 240 V AC/DC.
Light/dark on switching type, selectable for application flexibility.
Equipped with a sensitivity adjuster for fine-tuning detection.
Highly visible status LEDs for easy installation and operational monitoring.

Technical Specification Matrix

Parameter	Value
Effective Detection Range	0 to 17 m
Light Source	Modulated visible red LED
Operating Voltage	12 ... 240 V AC/DC
Output Type	Relay, 1 alternator (SPDT)
Switching Voltage	Up to 250 V AC/DC
Switching Current	Up to 2 A
Switching Frequency	25 Hz
Ambient Temperature Range	-30°C to +60°C
Degree of Protection	IP67
Housing Material	ABS plastic
Product Standard	EN 60947-5-2
Protection Class	II
Connection	Terminal
Programmable Time Functions	GAN, GAB, IAB, GAN-GAB, GAN-IAB
Switching Type	Light/dark on switchable

Industrial Applications

1. Conveyor Belt Material Detection and Sorting

This sensor can accurately detect the presence or absence of objects on a conveyor belt, even at varying distances within its 17m range. Its programmable time functions can be used for precise timing of sorting mechanisms or to prevent product jams, ensuring efficient material flow.

Problem Solved

Prevents product bottlenecks and ensures efficient material flow on long conveyor lines, especially in dusty or wet conditions (IP67 rating) and fluctuating temperatures (-30°C to +60°C). The relay output can directly control sorting gates or stop/start conveyor motors.

Object detectionConveyor systemsMaterial handlingSortingAutomationIP67Relay controlTiming functions

2. Automated Door/Gate Presence Sensing in Industrial Facilities

The sensor can be mounted on industrial doors or gates to detect vehicles or personnel entering or exiting, ensuring safety and automating access. Its wide operating voltage range allows for flexible integration into various power systems prevalent in industrial settings.

Problem Solved

Enhances safety by preventing doors/gates from closing on moving objects or people. The IP67 rating ensures reliable operation in challenging industrial environments exposed to dust and water, and the wide operating temperature accommodates varied facility conditions.

Access controlSafetyAutomated doorsGate automationPresence detectionIP67Wide voltage rangeIndustrial safety

3. Level Monitoring in Non-Contact Applications for Granular Material

By mounting the retroreflective sensor above a silo or tank, it can detect the material level by sensing the presence or absence of the reflector's return signal. The 0-17m range is suitable for medium to large containers storing granular or bulk materials.

Problem Solved

Provides reliable, non-contact level monitoring, reducing the risk of contamination or damage from direct contact sensors. Its robust design (IP67, -30°C to +60°C temp range) allows for deployment in harsh environments often associated with bulk material storage. The relay output can trigger alarms or control filling/emptying processes.

Level sensingBulk material handlingNon-contact detectionSilo monitoringTank levelProcess controlIP67Long range detection