Neptune Systems 2″ Flow Sensor FS200

Neptune Systems 2" Flow Sensor – accurate inline flow data for Apex systems

The Neptune Systems 2" Flow Sensor reports real-time flow to Apex for confident pump tuning. Built by Neptune Systems, it fits neatly within Automate & Monitor setups and large return manifolds.

Place the Neptune Systems 2" Flow Sensor in your control stack

Integrate it with Controllers for live readouts and alarms. Then pair it with Flood Control & Leak Sensors to spot issues before they snowball.

Neptune Systems 2" Flow Sensor highlights

• Measures 300–3000 GPH on 2" return lines

• Installs inline and connects to the FMM port

• Includes two unions that adapt BSPP threads to 2" slip PVC

• Confirms pump performance and valve adjustments

• Helps reveal clogs, swollen hoses, or fading output

Quick installation and setup

• Dry-fit unions, then solvent-weld the 2" slip sides

• Mount the sensor upright with arrow matching flow direction

• Plug the sensor cable into the FMM module

• Calibrate flow in Apex, then set alert thresholds

Specifications

• Pipe size: 2" slip PVC (both sides via included unions)

• Flow range: 300–3000 GPH

• Thread type at sensor: BSPP (adapted by the unions)

• Interface: FMM input to Apex

• Typical use: Return lines and large manifold legs

What’s included

• 1× Neptune Systems 2" Flow Sensor

• 2× BSPP-to-2" Slip Unions

Best practices for stable readings

• Keep the run straight for several inches before the sensor

• Avoid trapped air; purge microbubbles at startup

• Recheck unions after the first warm cycle

• Log baseline flow to spot drift over time

Most Frequrntly Asked Questions about the Neptune Systems 2" Flow Sensor

Does it require an Apex FMM?

Yes. The sensor reports through an FMM port to Apex.

Can I use it on flexible hose?

Use hard 2" PVC. If needed, transition from hose to PVC, then install.

How much straight pipe should I leave?

Aim for 6–10 inches of straight pipe before the sensor.

Will it restrict my return line?

Restriction is minimal when installed on full 2" plumbing.

Can I mount it horizontally?

Yes. Keep the body level and the arrow in the flow direction.

What if my readings fluctuate?

Purge air, confirm valve positions, and verify the FMM connection.

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