Neptune Systems MOS Magnetic Optical Sensor

Overview

The Neptune MOS (Magnetic Optical Sensor) is the modern upgrade to the original OS-1 Optical Sensor, redesigned with a compact form factor, improved durability, and enhanced waterproofing. Its built-in magnetic mount makes installation effortless, while the silicone-encased external magnet ensures a secure hold on glass or acrylic surfaces up to 1/2" thick. Designed for precise water level control, the MOS is ideal for auto-top-off systems, sump level monitoring, water storage applications, and high-level safety alerts.

Key Features

• Modern & Compact Design – Sleeker, more durable, and built to fit into tight spaces.

• Precise Water Level Monitoring – Uses infrared light reflection for accurate wet/dry state detection.

• Built-In Magnetic Mount – Strong, easy-to-position mounting system.

• Silicone-Encased Magnet – Protects against corrosion and ensures long-lasting strength.

• Completely Waterproof – Engineered to resist water intrusion into the sensor body.

• Versatile Applications – Perfect for ATOs, sump high-water alerts, or reservoir monitoring.

• Aquarium-Safe Installation – Works with glass or acrylic surfaces up to 1/2" thick.

Product Specifications

• Model: Neptune MOS (Magnetic Optical Sensor)

• Replaces: OS-1 Optical Sensor

• Sensor Type: Infrared reflected light optical sensor

• Mounting: Internal/external magnetic system

• External Magnet Protection: Silicone encased

• Wall Thickness Compatibility: Up to 1/4" (reservoir walls) / up to 1/2" (glass/acrylic tanks)

• Connection: Apex FMM port

• Applications: Auto-Top-Off, sump water level control, high-level alarms, storage monitoring