Rain Bird FS400P 4-Inch PVC Tee Flow Sensor

Rain Bird FS400P 4-Inch PVC Tee Flow Sensor

Brand: Rain Bird | SKU: FS400P

Product Overview

Add flow measurement to a 4-inch PVC irrigation line with the Rain Bird FS400P. The sensor is supplied in a solvent-weld tee, with a removable impeller insert for service. Its suggested 40–500 GPM range makes expected demand a key selection check, especially when smaller zones share a large mainline.

Key Features

• 4-inch PVC tee with solvent-weld socket ends.
• Impeller sensing with a removable insert.
• Designed for outdoor or underground use.
• Provides flow input through a compatible controller interface.

Common Uses

• Measuring flow in a compatible 4-inch PVC irrigation mainline.
• Supplying flow data for supported and configured monitoring or flow-management functions.

Technical Specifications

• Model: FS400P; factory part: M80107.
• Nominal connection: 4-inch PVC slip / solvent-weld socket ends.
• Meter body: Schedule 80 PVC tee.
• Suggested design flow range: 40–500 GPM.
• Model-specific maximum line pressure: 100 psi; maximum liquid temperature: 140°F. Apply the manufacturer’s pressure/temperature derating.
• Sensing method: impeller with removable sensor insert.
• Output: frequency signal proportional to flow.
• Calibration K-factor: 13.7424; offset: +0.2307.
• Straight pipe: at least 10 pipe diameters upstream and 5 downstream.
• Location: outdoor or underground, with access for service.
• Sensor and tee assembly; controller, interface, valves and installation materials are separate.

Dimensions

• Manufacturer-listed width: 7.38 inches.
• Manufacturer-listed height: 7.83 inches.

Compatibility & Installation Notes

Choose the sensor for expected station flow as well as pipe size. Select the exact model in the controller or enter its K-factor and offset when custom calibration is required.

Allow at least 10 pipe diameters of straight, unobstructed pipe upstream and 5 downstream. Point the flow arrow in the water-flow direction. On a horizontal line, keep the tee upright.

Remove the sensor insert before solvent-welding the tee. Keep the insert clean, follow the PVC cement curing instructions, then reinstall the insert and retainers as directed.

ESP-LXD installations use the appropriate sensor decoder; Rain Bird lists SD211TURF as the replacement for SD210TURF. ESP-LXMEF uses its Flow Smart Module. Other supported systems need their specified interface. Interface parts and controllers are separate.

Keep signal polarity correct and use suitable waterproof splices. Flow alarms and automatic shutoff depend on the controller settings and operating valves; the sensor alone does not stop water.

Frequently Asked Questions

Are the FS400P pipe ends threaded?

No. FS400P has nominal 4-inch PVC slip / solvent-weld socket ends.

What flow range should I use to select it?

Rain Bird lists a suggested 40–500 GPM design range. Check the actual flows of the stations being monitored, including the smallest zone.

How much straight pipe is required?

Allow at least 10 pipe diameters of unobstructed straight pipe upstream and 5 downstream.

Will it shut off a broken irrigation line by itself?

No. It reports flow to the compatible control system. Shutoff requires the correct interface, controller configuration and operating valves.

Why Buy from Big Frog Supply?

Choose FS400P when a 4-inch solvent-weld connection and a suggested 40–500 GPM measuring range match the job. Its upper design range exceeds FS300P’s 300 GPM range, while its 40 GPM lower design limit deserves attention on smaller zones. The Schedule 80 tee provides a ready connection into the line; verify that the location also has enough straight pipe and room to remove the insert for maintenance.