E3JK Square Photoelectric Sensor (Relay & Transistor Output)

Name: E3JK Square Photoelectric Sensor (Relay & Transistor Output)
Brand: DAIDISIKE
SKU: e3jk-square-photoelectric-sensor
Availability: InStock

Square photoelectric sensor with relay (3 A) or NPN/PNP transistor output — relay versions drive a load with no PLC or amplifier; transistor versions feed a PLC input directly.

E3JK Square Photoelectric Sensor (Relay & Transistor Output) - dimensional drawing

🔍 Click to enlarge · 1/7

Technical Specifications

Sensing modes	Diffuse-reflective, retro-reflective (with reflector), through-beam
Sensing distance — diffuse-reflective (DS30)	0.5 m or 1.5 m (±10%)
Sensing distance — retro-reflective (R4)	4 m (±10%)
Sensing distance — through-beam (5DM)	5 m (relay) / 15 m (transistor)
Output type	Internal relay (J/Z/A/DJ) or NPN/PNP transistor (M1-M4)
Relay operating voltage — J	90-250 VAC
Relay operating voltage — Z	10-30 VDC
Relay operating voltage — A/DJ	10-250 V AC/DC (universal)
Transistor operating voltage	10-30 VDC
Relay contact rating	3 A max.
Transistor output logic	NPN-NO (M1), NPN-NC (M2), PNP-NO (M3), PNP-NC (M4)
Wiring	Relay versions: 5-wire; transistor versions: 3-wire
Sensitivity adjustment	Trimmer potentiometer
Degree of protection	IP55
Operating temperature	-25°C to 65°C
Cable length	2 m

Overview

E3JK is a series of square-body photoelectric sensors offered in three sensing modes — diffuse-reflective, retro-reflective (with reflector), and through-beam (opposed) — and two output technologies: an internal relay (AC, DC, or universal AC/DC power) and NPN/PNP transistor (10-30 VDC, 3-wire) output. It suits panel builders, machine retrofitters, and OEMs who need a photoelectric switch that can either drive a load directly (relay) or feed a PLC/controller input (transistor) using the same housing footprint.

The series covers diffuse-reflective detection at 0.5 m or 1.5 m (±10%), retro-reflective detection at 4 m (±10%) using a reflector board, and through-beam detection at 5 m (relay) or up to 15 m (transistor). Relay-output versions switch loads up to 3 A directly and accept 90-250 VAC, 10-30 VDC, or a universal 10-250 V AC/DC supply, while transistor versions operate on 10-30 VDC in NPN or PNP, normally-open or normally-closed logic.

Features & Benefits

Relay Output Drives Loads Directly

J/Z/A(DJ) versions have a built-in relay (3 A max. contact rating) that switches small contactors, solenoid valves, or alarm lamps directly. No PLC or amplifier is required, which is useful where there is no PLC or DC power supply on site.

One Series, Any Power Supply

The J suffix runs on 90-250 VAC, the Z suffix on 10-30 VDC, and the A/DJ suffix accepts a universal 10-250 V AC/DC supply, so the same sensing mode can match almost any panel power available on site.

Relay and Transistor Share One Housing

Diffuse-reflective and retro-reflective models are offered in all four transistor logic combinations (NPN-NO, NPN-NC, PNP-NO, PNP-NC) in the same housing as the relay versions, so upgrading from relay to transistor control does not require re-drilling the mounting bracket.

Three Sensing Modes in One Family

Diffuse-reflective (0.5 m / 1.5 m ±10%) suits close-range detection without a reflector, retro-reflective (4 m ±10%) uses a reflector board for longer range, and through-beam (5 m relay / 15 m transistor) gives the longest, most reliable detection distance.

Adjustable Sensitivity

An onboard trimmer potentiometer lets you fine-tune the detection threshold on site to match different target sizes, colors, or reflectivity.

IP55 Protection, Wide Temperature Range

IP55 degree of protection suits general industrial environments with dust and occasional water splash, and a -25°C to 65°C operating range tolerates unheated workshops and moderately hot equipment enclosures.

Applications

Conveyor Object Detection — Diffuse or through-beam modes reliably flag opaque objects passing a fixed point on a conveyor line, for object-present or object-passing detection.

AC-Powered Legacy Machine Retrofits — The J-suffix relay version runs directly on 90-250 VAC and switches the load itself, so old machines can be retrofitted without adding a separate DC power supply.

Direct Actuation of Solenoid Valves, Contactors, or Alarm Lamps — The built-in relay (3 A max.) switches these loads directly, without an external PLC or contactor relay.

Packaging and Filling Line Counting — Repeatable diffuse or retro-reflective detection counts discrete opaque items such as boxes or bottles passing the beam.

Gate and Doorway Detection at Longer Range — The through-beam version reaches up to 15 m (transistor) or 5 m (relay), suited to wide openings such as gates and passageways.

Mid-Range Detection with a Reflector Board — Retro-reflective mode (4 m) uses a dedicated reflector board, reducing background interference compared with pure diffuse sensing.

PLC Digital Input Integration — M1-M4 transistor versions provide NPN/PNP, NO/NC 3-wire outputs matched to common PLC input cards for panel and control-cabinet integration.

Sites Without Dedicated 24 VDC Control Power — J and A/DJ versions accept mains or universal AC/DC power directly, avoiding the need for a separate power supply unit.

Models & Ordering Information

Diffuse-Reflective (DS30, 0.5 m / 1.5 m ±10%)

E3JK-DS30JE3JK-DS30ZE3JK-DS30A/DJE3JK-DS30M1E3JK-DS30M2E3JK-DS30M3E3JK-DS30M4

Retro-Reflective (R4, 4 m ±10%, with reflector)

E3JK-R4MJE3JK-R4MZE3JK-R4A/DJE3JK-R4M1E3JK-R4M2E3JK-R4M3E3JK-R4M4

Through-Beam (5DM, 5 m relay / 15 m transistor)

E3JK-5DMJE3JK-5DMZE3JK-5A/DJE3JK-5DM1E3JK-5DM3

Through-beam transistor versions are available only in normally-open (NO) logic; E3JK-5DM2 and E3JK-5DM4 (normally-closed) do not exist in this series.

How to Select

For close-range detection without a reflector, choose diffuse-reflective DS30 (0.5 m or 1.5 m ±10%).
For mid-range detection where a reflector board can be mounted, choose retro-reflective R4 (4 m ±10%).
For the longest range and highest reliability with separate emitter/receiver mounting, choose through-beam 5DM (5 m relay / 15 m transistor).
To drive a contactor, solenoid valve, or alarm lamp directly from AC mains, choose relay output J (90-250 VAC).
If only DC power is available on site, choose relay output Z (10-30 VDC).
If the site power type is uncertain or both AC and DC must be supported, choose relay output A/DJ (10-250 V AC/DC universal).
To feed a PLC or controller digital input, choose transistor output M1 (NPN-NO), M2 (NPN-NC), M3 (PNP-NO), or M4 (PNP-NC), 10-30 VDC.
Note: the through-beam (5DM) transistor line only offers M1 (NPN-NO) and M3 (PNP-NO) — normally-closed 5DM2/5DM4 do not exist, so check before ordering.
Diffuse-reflective (DS30) and retro-reflective (R4) transistor versions offer all four M1-M4 combinations (NO/NC, NPN/PNP).
Relay versions are 5-wire; transistor versions are 3-wire. All models use a 2 m integral cable that connects directly into the control cabinet.

📘 Need the full method? NPN vs PNP Sensor Outputs Explained

When NOT to specify the E3JK — and what to use instead

A Normally-Closed (NC) output is required on the through-beam (5DM) transistor version

Why not: The through-beam transistor line only offers NO logic (M1/M3) - E3JK-5DM2 and E3JK-5DM4 (NC) do not exist in this series.

Use instead: the diffuse-reflective (DS30) or retro-reflective (R4) E3JK models, which offer all four M1-M4 NO/NC combinations

The retro-reflective (R4) model must detect a shiny, mirror-like, or highly reflective target

Why not: Retro-reflective sensing compares reflected light against the reflector board's signature - a mirror-like target can read the same as the reflector itself; no polarizing-filter option is documented for this series.

Use instead: a background-suppression model that senses the object directly, such as BGS-CX441/CX442

Outdoor washdown, high-pressure spray, or heavy wet exposure

Why not: This series is rated IP55 - dust and splash protected, not rated for high-pressure washdown or submersion.

Use instead: the BGS-CX61, which is IP67-rated

Detecting very small parts or narrow features

Why not: No minimum detectable object size is published for the E3JK series; its sensing distances (0.5-15 m) are sized for object/box/bottle-scale detection.

Use instead: the DX-15/30 ultra-thin series (1 mm minimum detectable object) or the strip-beam DK-D461/D561 for narrow targets

Personnel guarding at a gate, doorway, or other access point

Why not: No safety rating or safety certification is published for the E3JK series, despite gate/doorway detection being a listed application.

Use instead: a certified safety light curtain (e.g. DQC/DQA series) for personnel protection

Specifications we do not publish yet

We only publish a figure once we are confident it is true. The items below are still being validated through further testing and real-world customer feedback, so for now we would rather leave them open than guess. If one of them matters to your design, ask us for the latest validated status.

Minimum detectable object size
Hysteresis
MTBF
Light source type/wavelength (not specified as infrared, visible, or laser)
Reflector part number for the retro-reflective (R4) variant
Cable connector type (2 m cable length is stated, connector type is not)
Certification status (documents said to be available on request but not specified)

Frequently Asked Questions

What is the maximum load current of the E3JK relay output?

The built-in relay contact is rated for a maximum of 3 A.

Can the E3JK run directly on AC mains power?

Yes. The J-suffix versions (e.g. E3JK-DS30J) accept 90-250 VAC directly, so the sensor's internal relay can switch a load without any external power supply conversion.

What is the difference between the J, Z, and A/DJ output suffixes?

J = internal relay powered by 90-250 VAC; Z = internal relay powered by 10-30 VDC; A/DJ = internal relay powered by a universal 10-250 V AC/DC supply.

What sensing distances does the E3JK series cover?

Diffuse-reflective (DS30) covers 0.5 m or 1.5 m (±10%); retro-reflective (R4) covers 4 m (±10%); through-beam (5DM) covers 5 m for relay versions and up to 15 m for transistor versions.

Are NPN and PNP transistor outputs both available?

Yes, for the diffuse-reflective and retro-reflective models, all four combinations are available: NPN-NO (M1), NPN-NC (M2), PNP-NO (M3), PNP-NC (M4). The through-beam model is only available in NO logic: NPN-NO (M1) and PNP-NO (M3).

Is there a through-beam NC (normally closed) transistor version?

No. E3JK-5DM2 and E3JK-5DM4 do not exist in this series — the through-beam transistor line is limited to normally-open (NO) logic only.

What is the degree of protection of the E3JK sensor?

IP55.

What is the operating temperature range?

-25°C to 65°C.

How is sensitivity adjusted?

Via an onboard trimmer potentiometer, allowing the detection threshold to be fine-tuned on site.

What cable length does the E3JK come with?

A 2 m integral cable.

Can you provide certification documents for the E3JK sensor?

Certification documents are available on request.

Works Well Together

On the same machine or line, E3JK is typically ordered together with: Proximity Sensors · Laser Switch Sensors · Relay & Timer Modules

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