Home › Manufacturers › Allen Bradley › 871A-TR4-D1

Allen Bradley

Allen Bradley 871A-TR4-D1 Inductive Proximity Sensor, 4mm, NC

Allen Bradley 871A-TR4-D1 Inductive Proximity Sensor

● In Stock 12-Mo Warranty Same-Day Dispatch Ships Worldwide 🎖 Veteran-Owned

In Stock — Ready to Ship

ManufacturerAllen Bradley

Part number871A-TR4-D1

Sensing Range 4mm

Output NPN

Contact Type Normally Closed (NC)

Voltage 10-30VDC

Get a price for 871A-TR4-D1

Response within 1 business hour

🛡

12-month warranty

All units tested

⚡

Same-day dispatch

Order by 2pm CST

🌐

Worldwide delivery

US, EU, Asia, Middle East

🎖

Veteran-owned

CAGE: 9NK75

4mm sensing distance NPN output Normally Closed contacts M12 threaded stainless steel body 10-30VDC power High reliability

Product description

The Allen Bradley 871A-TR4-D1 is an inductive proximity sensor engineered for robust object detection in demanding industrial environments. It features a 4mm sensing distance and provides an NPN output with normally closed (NC) contacts. Operating on a 10-30VDC power supply, this sensor is housed in a standard M12 threaded stainless steel casing for durability.

This proximity sensor is ideal for applications requiring fail-safe operation, such as detecting the presence or absence of an object where an open circuit should indicate detection. Common uses include safety interlocks, gate control, and end-of-travel sensing in automated machinery across sectors like automotive, material handling, and manufacturing.

Stanlo Automation, a veteran-owned surplus parts distributor, offers the Allen Bradley 871A-TR4-D1 at competitive prices. We provide a reliable source for hard-to-find and essential industrial automation components, ensuring your operations continue smoothly with quality parts.

Technical specifications

Sensing Range	4mm
Output	NPN
Contact Type	Normally Closed (NC)
Voltage	10-30VDC
Body Style	M12 Threaded
Body Material	Stainless Steel
Frequency Response	1000 Hz

Common applications

Safety interlocks

Gate control

End-of-travel sensing

Presence/absence detection

Automated machinery

Material handling

Compatible systems

PLC automation systems DC control circuits Machine safety systems

Also known as

871A-TR4-D1 sensor Allen Bradley proximity switch 871A NC sensor NPN NC proximity sensor

Replaces / compatible with

Replaces other Allen Bradley 871A series sensors with NPN NC output and 4mm sensing range.

Technical note

Expert tip

The NPN NC configuration is suitable for safety-related applications where loss of detection signal should trigger a specific action.

What happens next?

Email confirmation

Immediate receipt acknowledgment sent to you

Account manager assigned

Confirms your part's spec and condition

Your quote delivered

Tailored to your specific requirements

Frequently asked questions

How does the normally closed (NC) output of the 871A-TR4-D1 function?

With the 871A-TR4-D1, the NPN output is closed (conducting) when no metallic object is detected. When a metallic object enters the sensing range, the output opens (stops conducting), signaling its presence.