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OMRON Photoelectric Sensor: M18 Threaded, Built-in Connector, 4 - Pin M12 Connector - Cylindrical Sensors with Built-in Connectors
OMRONCylindrical Sensors with Built-in Connectors

OMRON Photoelectric Sensor: M18 Threaded, Built-in Connector, 4 - Pin M12 Connector

The OMRON E3RA-RN21 is an M18 threaded cylindrical photoelectric sensor with a built-in 4-pin M12 connector. It operates on a 10-30V DC supply and features an NPN output. This sensor is designed for industrial…

SKU 3G-OTH-159705

Also listed as: E3RARN21 · E3RA RN21

Brand
OMRON
Item
Photoelectric Sensor: M18 Threaded, Built-in Connector, 4 - Pin M12 Connector
Category
Cylindrical Sensors with Built-in Connectors
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

OMRON
Manufacturer Part Number
E3RA-RN21
Type
Built-in Connector, NPN
DC
10-30V
Pin M12 Connector
4 -

Technical Documents

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OMRON Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The OMRON E3RA-RN21 is an M18 threaded cylindrical photoelectric sensor with a built-in 4-pin M12 connector. It operates on a 10-30V DC supply and features an NPN output. This sensor is designed for industrial automation applications requiring reliable object detection.

Frequently Asked Questions

What is the OMRON E3RA-RN21 photoelectric sensor used for?

The OMRON E3RA-RN21 is used for reliable object detection in industrial automation, such as presence sensing, positioning, and counting on conveyor lines or packaging machinery. Its M18 threaded cylindrical design suits tight spaces, and the built-in M12 connector simplifies wiring in factory environments.

What are the specifications of the OMRON E3RA-RN21?

The OMRON E3RA-RN21 is an M18 threaded cylindrical photoelectric sensor with a built-in 4-pin M12 connector. It operates on 10-30V DC supply and provides NPN output. The sensor is designed for reliable object detection in industrial automation applications.

Where to buy the OMRON E3RA-RN21 worldwide?

You can source the OMRON E3RA-RN21 through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time; we supply genuine OMRON sensors for your automation needs.

How to install the OMRON E3RA-RN21 sensor?

Mount the sensor using the M18 threaded body into a suitable bracket or hole. Connect the 4-pin M12 connector to a compatible cable, ensuring 10-30V DC power and proper NPN wiring. Align the sensor with the target and adjust sensitivity if needed. Follow standard industrial safety practices during installation.

Used in

Common applications for OMRON
Automotive assembly lines — OMRON G2RV-ST500 AC/DC24 slim relays for compact control panel switching
Packaging machinery — OMRON E2E-X5Y1-M1 inductive proximity sensors for position detection of metal parts
HVAC systems — OMRON LY4-DC12 general-purpose relays for fan and compressor control
High-temperature ovens — OMRON E32-D51 fiber-optic cables for non-contact temperature sensing
Material handling — OMRON D4CC3002 limit switches for conveyor belt end-of-travel detection
Machine tool safety — OMRON TZ-1GV22 snap-action switches for interlock and guard monitoring

OMRON Products

3G Electric supplies OMRON cylindrical sensors with built-in connectors. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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