E3JK Relay-Output Square Photoelectric Switch
The E3JK footprint the industry already trusts — three sensing modes and a built-in 3 A relay that lets old AC machines gain a photoelectric eye without adding a PLC or a DC supply.
- Diffuse 0.5 / 1.5 m · retro-reflective 4 m · through-beam 5–15 m
- Relay output switches 3 A loads directly
- Supply options: 90–250 VAC, 10–30 VDC, universal AC/DC
- NPN/PNP transistor versions (M1–M4) for PLC inputs
- IP55, −25 °C to +65 °C, trimmer sensitivity
Product Overview
The E3JK format is one of the most widely wired photoelectric switch footprints in the world, and our factory-direct E3JK series keeps that familiarity deliberate: the same square housing style, the same model-code logic, the same three sensing modes — produced as a localized, readily stocked supply option for importers and maintenance buyers who need the format without the long supply chain.
What sets E3JK apart from compact DC-only sensors is the output stage. Relay versions carry a 3 A contact and accept 90–250 VAC (J), 10–30 VDC (Z) or a universal 10–250 V AC/DC (A/DJ) supply, so the sensor can both power up from whatever the site offers and switch the load itself. Transistor versions (M1–M4) cover the full NPN/PNP × NO/NC matrix on 10–30 VDC for PLC integration — in the same housing, so upgrading control philosophy does not mean re-drilling brackets.
Sensing modes: diffuse-reflective at 0.5 m or 1.5 m (±10%), retro-reflective at 4 m (±10%) with a reflector board, and through-beam at 5 m (relay) or up to 15 m (transistor). All versions have an on-body trimmer, IP55 protection, a −25 °C to +65 °C rating and a 2 m integral cable.
Three Sensing Modes at a Glance
Model Selection Table
| Sensing Mode | Relay Output Models | Relay Supply | Transistor Models (10–30 VDC) |
|---|---|---|---|
| Diffuse-reflective, 0.5 m / 1.5 m ±10% | E3JK-DS30J · E3JK-DS30Z · E3JK-DS30A/DJ | J: 90–250 VAC · Z: 10–30 VDC · A/DJ: 10–250 V AC/DC | DS30M1 (NPN NO) · DS30M2 (NPN NC) · DS30M3 (PNP NO) · DS30M4 (PNP NC) |
| Retro-reflective, 4 m ±10% (reflector) | E3JK-R4MJ · E3JK-R4MZ · E3JK-R4A/DJ | J: 90–250 VAC · Z: 10–30 VDC · A/DJ: 10–250 V AC/DC | R4M1 · R4M2 · R4M3 · R4M4 |
| Through-beam, 5 m relay / 15 m transistor | E3JK-5DMJ · E3JK-5DMZ · E3JK-5A/DJ | J: 90–250 VAC · Z: 10–30 VDC · A/DJ: 10–250 V AC/DC | 5DM1 (NPN NO) · 5DM3 (PNP NO) — NC codes do not exist |
Relay versions wire with 5 conductors, transistor versions with 3; all models ship with a 2 m integral cable and trimmer sensitivity adjustment.
Technical Specifications
| Sensing modes | Diffuse-reflective / retro-reflective (with reflector) / through-beam |
|---|---|
| Sensing distance | DS30: 0.5 m or 1.5 m ±10% · R4: 4 m ±10% · 5DM: 5 m (relay) / 15 m (transistor) |
| Output | Built-in relay, 3 A max. contact — or NPN/PNP transistor, NO/NC (M1–M4) |
| Supply voltage | Relay J: 90–250 VAC · relay Z: 10–30 VDC · relay A/DJ: 10–250 V AC/DC · transistor: 10–30 VDC |
| Sensitivity adjustment | Trimmer potentiometer |
| Protection rating | IP55 |
| Operating temperature | −25 °C to +65 °C |
| Cable | 2 m integral; relay 5-wire, transistor 3-wire |
| Light source / min. target size | Contact factory |
General-purpose sensing component — not an IEC 61496-certified safety component; never use it alone for personnel protection.
Typical Applications
Legacy AC Machine Retrofits
The J version runs straight off 90–250 VAC and its 3 A relay drives the load itself — no 24 V supply, no PLC required.
Conveyor & Packaging Counting
Diffuse or retro-reflective heads count boxes and bottles at fixed points, with a trimmer to set the threshold on site.
Direct Load Switching
Solenoid valves, small contactors and alarm stacks switch directly from the built-in relay contact (3 A max.).
Wide Gates & Passages
Through-beam models span 5 m (relay) to 15 m (transistor) across doorways, gates and wide conveyor aisles.
Frequently Asked Questions
Is this compatible with existing E3JK-type installations?
Yes — that is the point of the series. It follows the familiar E3JK model-naming convention, square housing format and wiring conventions that panel builders worldwide already know, produced and stocked at our own Foshan factory as a localized supply option. Mounting bracket geometry and model suffix logic (DS30 / R4 / 5DM, J / Z / A-DJ / M1-M4) follow the established pattern, so a like-for-like swap normally needs no re-engineering. Always verify your existing model code against the selection table before ordering.
When should I choose the relay output instead of a transistor output?
Choose the relay versions (J / Z / A-DJ) when there is no PLC in the loop and the sensor itself must switch the load: the built-in relay is rated 3 A, enough for a small contactor, solenoid valve or alarm lamp. Choose the transistor versions (M1-M4) when the sensor feeds a PLC digital input — NPN or PNP, NO or NC, on 10-30 VDC.
What supply voltages are available?
Three relay supply options: J = 90-250 VAC (mains direct), Z = 10-30 VDC, and A/DJ = universal 10-250 V AC/DC for sites where the available power is uncertain. All transistor versions (M1-M4) run on 10-30 VDC.
What sensing ranges do the three modes cover?
Diffuse-reflective (DS30): 0.5 m or 1.5 m ±10%, no reflector needed. Retro-reflective (R4): 4 m ±10% against a reflector board. Through-beam (5DM): 5 m for relay versions and up to 15 m for transistor versions, using a separate emitter and receiver.
Is there a normally-closed through-beam transistor model?
No. The through-beam transistor line offers NO logic only — E3JK-5DM1 (NPN NO) and E3JK-5DM3 (PNP NO). Codes 5DM2/5DM4 do not exist in this series. If you need NC logic, use the diffuse (DS30) or retro-reflective (R4) versions, which come in all four M1-M4 combinations.
Can it work outdoors or in washdown areas?
It is rated IP55 — dust-protected and splash-resistant, suitable for general factory floors, with a wide -25 to 65 °C operating range. It is not rated for high-pressure washdown or immersion; for those stations ask us about IP67-class alternatives.
Can the E3JK be used for machine guarding?
No. It is a general-purpose object-detection switch, not an IEC 61496-certified safety component, and must never be the device protecting an operator — even at gates and doorways it may only signal, not safeguard. Use a certified safety light curtain (e.g. DQC series) for guarding.
How do I order, and what are the export terms?
Send the exact model codes (e.g. E3JK-DS30J x 50, E3JK-5DM1 x 20) with your destination port. Small trial orders are generally accepted; MOQ, lead time, packing and available certification documents are confirmed at quotation, factory-direct from Foshan.
Specs reviewed by Engineer Cai, Senior Application Engineer. See certificates.