LV-S31 Adjustable Reflective Sensor | Keyence

Keyence LV-S31 Adjustable Distance Definite Reflective Laser Sensor Head for LV-N Series Amplifiers

Product Introduction

The LV-S31 belongs to Keyence's LV-S ultra-small series of digital laser sensor heads. This diffuse-reflective model uses adjustable distance definite reflective sensing to suppress background objects and detect targets within a 50 to 200 mm range. Its visible red semiconductor laser operates at 655 nm and meets Class 1 safety standards under FDA CDRH and IEC 60825-1 regulations. Because the sensor head receives power and signal processing through the amplifier, it requires no separate power supply or output circuitry of its own. This design simplifies wiring and reduces the footprint at the sensing point.

Technical Specifications

The LV-S31 uses a visible red semiconductor laser with a wavelength of 655 nm. The detecting distance is adjustable from 50 to 200 mm, letting users set a definite reflective range that ignores objects beyond the chosen distance. The laser classification is Class 1 according to FDA CDRH Part 1040.10 and IEC 60825-1, so the unit is safe under normal operating conditions without extra protective measures. The sensor head features a glass-reinforced plastic housing that balances durability with low weight. Since the LV-S31 is a sensor head only, it contains no built-in communication ports or output transistors. All signal output and communication functions are handled by the connected LV-N amplifier unit.

Mechanical and Environmental Parameters

The sensor head operates within an ambient temperature range of 0 to +50 °C with no freezing permitted. Its compact glass-reinforced plastic enclosure keeps the unit at approximately 75 g, minimizing mechanical load on mounting brackets and moving fixtures. Specific dimensions and ingress protection ratings are not published for this model. The LV-S31 connects to the amplifier through a dedicated cable, so users should verify cable length and routing space during installation planning. For environments with fine particles or coolant mist, users should confirm suitability with Keyence technical documentation, as the sensor head does not carry a published IP rating.

Installation Guide

First, mount the LV-S31 using the appropriate bracket for your application. The ultra-small form factor allows placement in tight spaces where standard sensor heads cannot fit. Next, connect the sensor head to an LV-N series amplifier using the dedicated cable. Ensure the connector is fully seated and the locking mechanism engages. After powering the amplifier, set the definite reflective distance within the 50 to 200 mm adjustment range. Specifically, adjust the distance so the target falls inside the detection zone while background objects stay outside it. During commissioning, verify that the laser spot aligns with the target and that ambient light does not interfere with detection. Finally, tighten all mounting hardware and perform a test cycle to confirm consistent output signals.

Packaging List

• LV-S31 sensor head × 1

• Dedicated connection cable × 1

• Mounting bracket (standard) × 1

• Installation screws × 1 set

• Product manual × 1

FAQ

Q1: Does the LV-S31 work without an LV-N amplifier?
No. The LV-S31 is a sensor head only. It requires an LV-N series amplifier to supply power and process the detection signal.

Q2: What does "adjustable distance definite reflective" mean?
This sensing method lets users define a detection distance between 50 and 200 mm. Targets inside that range trigger output, while background objects beyond it are ignored.

Q3: How does the LV-S31 differ from other LV-S heads?
The LV-S31 offers adjustable distance definite reflective sensing for background suppression. Other heads, like the LV-S41, use fixed diffuse-reflective detection over longer ranges.

Q4: What laser class is this product?
The LV-S31 is a Class 1 laser product under FDA CDRH Part 1040.10 and IEC 60825-1. It is safe for normal operation without special eye protection.

Q5: How fast can you ship this item?
We ship via Fedex, UPS, and DHL. In-stock orders typically dispatch within 1–3 business days after payment confirmation.