# Wired optical endstop

> Wired optical endstop for 3D printers and CNC, based on the TCST2103 sensor (infrared optical barrier, 3.1mm slot). Features 3 pins (S, V, G), digital output, 5V supply and an 800mm cable with connector included. Compatible with Arduino UNO/Nano/Mega and control boards such as RAMPS 1.4, MKS, Melzi, used for home detection and limiting travel on X/Y/Z axes.

- Page: https://sigmanortec.ro/en/wired-optical-endstop
- Price: 8.47 RON
- Availability: In stock; 1-2 zile
- Reference: 22213 · EAN: 5940920792416
- Category: 3D and CNC printers > 3D Printer Sensors
- Package (shipping data): 0.008 kg
- Updated: 2026-09-14
- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Prices: RON, VAT included; prices and stock as of 2026-10-22 02:22 (Europe/Bucharest)

## Description

Infrared optical travel limiter for 3D printers and CNC, ensures precise detection of travel ends for XY Z axes. Uses TCST2103 sensor for fast and stable switching, has 3 pins for simple connection, includes 800 mm cable with connector, compatible with Arduino and other development boards.
RepRap optical infrared limit switch, equipped with a TCST2103 sensor, intended for detecting the home position and limiting axis travel on 3D printers and CNC machines. Its operation is based on an infrared optical barrier formed by an emitter LED and a receiver phototransistor, placed face to face on the two arms of the sensor. When a flag mounted on the moving axis enters the sensor slot and interrupts the infrared beam, the module output changes its logic state, signaling the control board that the travel limit has been reached. As a contactless system, there is no mechanical contact wear and no debounce effect specific to microswitches, which provides better homing repeatability compared to classic mechanical limit switches.
The module comes with an 800mm cable and connector, ready to connect to the control board, and has three pins for power, ground, and signal. It is compatible with Arduino boards (UNO, Nano, Mega), as well as common 3D printer and CNC control boards such as RAMPS 1.4, MKS, Melzi, or other platforms that accept digital endstop inputs. Many versions also include a status LED that visually indicates when the beam is interrupted, useful for mechanically adjusting the sensor position. The board is easy to mount through the PCB mounting holes, and the flag that interrupts the beam can be made from a simple 3D-printed part or a thin sheet of metal.
Specifications:
Optical sensor: TCST2103
Sensor type: infrared transmissive optical barrier
Sensor slot width: 3.1mm
Number of pins: 3
Supply voltage: 5V
Output type: digital (logic level)
Cable length: 800mm
Connector: included, mounted on cable
Applications: 3D printers, CNC machines, positioning systems
Pinout:
Pin
Meaning
Connection
S
Output signal
Digital pin of the development board
V
+5 V supply
5 V
G
Ground
GND
Usage:
Mount the module on the machine frame, aligned with the axis travel limit, using the mounting holes on the board.
Install a flag (tab) on the moving part of the axis so that it cleanly enters the sensor slot without touching its arms.
Connect pin V to 5V, pin G to GND, and pin S to a digital pin of the development board or to the corresponding endstop input on the control board.
Power the system and check the status LED or the signal pin reading by manually moving the flag in and out of the sensor slot.
Configure the endstop logic in the firmware (Marlin, Klipper, or other firmware), reversing the state if the switching direction does not match.
Run a home command on the respective axis and verify that movement stops correctly at the desired point.
Fine-tune the module position on the frame to set the exact home position of the axis.