The Magnetic Optical Sensor replaces our optical sensor with magnet and offers an improved look, feel, and magnetic design that also lends itself to help prevent water incursion into the sensor.
This sensor plugs into your FMM and, using reflected infrared light, will signal your Apex when it changes state from being wet to dry or dry to wet. This sensor can be used for constructing your own ATO (auto-top-off), as a high-level warning sensor in your sump, water storage level sensor, and much more. The sensors can be mounted into custom brackets or through a hole in a vessel. Included are a fastening nut and silicone washer. The MOS’ wire is 5 meters in length
The Neptune Systems Magnetic Optical Sensor (MOS) is the latest iteration of Neptune Systems' popular optical water level sensor, designed for superior reliability and ease of use in controlling and monitoring water levels in aquariums. It is an evolution of the previous OS-1M (Optical Sensor with Magnet Mount), featuring an improved design.
Key Features and Functions of the MOS:
Advanced Optical Sensing Technology:
The MOS utilizes an infrared (IR) optical sensor to detect the presence or absence of water. It works by emitting an IR light beam; when water is present, the light is refracted away, and when water is absent (dry), the light reflects back to the sensor. This simple, binary (on/off) detection is highly reliable and less prone to mechanical failures or sticking issues that can plague traditional float switches.
Integrated Magnetic Mount (Improved Design):
The "Magnetic" in MOS refers to its built-in magnetic mounting system. The sensor is enclosed in a compact, waterproof housing that has an integrated magnet. This allows for incredibly easy and flexible mounting on the inside of your sump, aquarium, or reservoir glass/acrylic, secured by a corresponding magnet on the outside.
Key improvements over previous versions: The MOS features a redesigned structure that is more compact, allowing it to fit into tighter spaces. It also has a silicone-encased external magnet for better grip and to prevent scratching your tank walls. The design is specifically aimed at preventing water incursion into the sensor's internal circuitry, which enhances long-term reliability and waterproofness.
Wall Thickness Compatibility: It is suitable for glass or acrylic walls up to 1/2" (approximately 12.7 mm) thick, though some older documentation might still refer to 1/4". The improved magnet allows for thicker walls.
Binary State Detection:
Like its predecessors, the MOS is a "binary" sensor: it's either OPEN (dry, no water detected) or CLOSED (wet, water detected). This makes it perfect for triggering pumps or alarms when a specific water level is reached or dropped.
Direct FMM Module Connection:
The MOS plugs directly into one of the four universal sensor ports on a Neptune Systems FMM (Fluid Monitoring Module). The FMM acts as the crucial interface, relaying the sensor's wet/dry status to your Apex controller.
Seamless Apex Fusion Integration:
Once connected and recognized by your Apex, the real-time status of the MOS (e.g., "ATO_Sensor is OPEN" or "ATO_Sensor is CLOSED") is displayed on your Apex Fusion dashboard.
Apex Fusion automatically logs all changes in the sensor's state, providing a historical record of water level events.
Essential for Automation and Safety:
The MOS is a cornerstone for many critical automation and safety routines:
Automatic Top-Off (ATO): This is its most common and vital application. An MOS placed at your desired sump water level can precisely turn an ATO pump (like the PMUPV2) ON when the water level drops (MOS goes DRY) and OFF when the level is restored (MOS goes WET).
High Water Level Safety: Place an MOS higher in your sump or display tank as a failsafe. If water rises unexpectedly (e.g., due to return pump failure or an overfilling ATO), the sensor will go WET and can trigger an audible alarm, send notifications, and/or shut off pumps to prevent an overflow.
Low Water Level in Reservoir: Position an MOS near the bottom of your RODI water reservoir. When it goes DRY, it can send an alert to your phone, notifying you to refill your top-off water.
Skimmer Cup Full Alarm: Place it inside your protein skimmer's waste collection cup. When the cup fills and the sensor goes WET, it can shut off the skimmer pump to prevent spills.
Custom Control: The binary nature allows for diverse applications where a simple ON/OFF switch based on water presence is needed.
Compatibility:
The MOS is compatible with all Neptune Systems Apex controllers that utilize an FMM module, including:
Apex A1, A2, and A3 series controllers (e.g., Apex, Apex EL, Apex Pro, Apex Jr.).
The A3 Apex models now even include a MOS and LD-2 sensor directly with the base unit, making it even easier to get started with critical water level monitoring.
Installation and Setup:
Placement: Determine the precise water level you want to monitor or control (e.g., the normal operating level of your sump, a high-level overflow point, or a low-level alert point in a reservoir).
Mounting: Clean the internal and external surfaces of the glass or acrylic where the sensor will be mounted. Place the MOS's internal magnetic half on the inside and match it with the external magnet on the outside, ensuring the optical eye is positioned at your desired water level.
Connection: Plug the cable from the MOS into any available sensor port on your Neptune Systems FMM module.
Configuration in Apex Fusion:
Access your Apex Fusion dashboard. Your Apex will typically auto-detect the connected MOS.
Go to the FMM's configuration page and the specific port where the MOS is connected. Give the sensor a clear, descriptive name (e.g., "Sump_ATO_Low," "Sump_High_Safety," "RODI_Reservoir_Low").
Utilize the "Tasks" wizard within Apex Fusion (e.g., "Auto Top-Off Kit" or "Add a Level Sensor") to easily set up your desired automation logic, alerts (email, SMS, push), and pump control based on the sensor's OPEN/CLOSED state.
The Neptune Systems Magnetic Optical Sensor (MOS) is a highly reliable, compact, and user-friendly optical sensor that is indispensable for automating crucial water level management tasks and enhancing the overall safety and stability of your aquarium system.
