Rain Bird PSI-M-40 pressure regulator with constant 2.8 bar outlet pressure

Reliable pressure reduction to 2.8 bar

The Rain Bird PSI-M-40 provides controlled water pressure of 2.8 bar (40 psi) in irrigation systems. The outlet pressure is factory preset, eliminating the need for additional adjustment after installation. It is suitable for irrigation zones where components need to operate with a defined and consistent water pressure.

Within its specified operating range, the regulator responds to changes in inlet pressure and water flow. This helps maintain the downstream pressure at the intended level while protecting connected irrigation components from unnecessarily high supply pressure.

Controlled pressure for irrigation systems

Suitable operating pressure is an important requirement for the reliable performance of drippers, dripline, micro-sprays and other irrigation components. If the available supply pressure is higher than required, the PSI-M-40 can be installed upstream of the corresponding irrigation zone.

With its preset outlet pressure of 2.8 bar, this model is suitable for applications requiring more pressure than the PSI-M versions rated at 1.0, 1.4, 1.8 or 2.1 bar. The appropriate pressure level should always be selected according to the specifications of the downstream irrigation components.

No manual pressure adjustment required

Pressure regulation is performed mechanically by a diaphragm. As a result, the PSI-M-40 requires no electrical power, batteries or connection to an irrigation controller. The required outlet pressure is preset and cannot be accidentally changed during operation.

This design makes the regulator straightforward to operate. Once correctly installed, pressure regulation takes place automatically whenever water flows through the unit.

¾" connections for straightforward installation

The Rain Bird PSI-M-40 has a ¾" female threaded connection on both the inlet and outlet. Suitable threaded fittings can therefore be used to integrate the regulator into the supply line of an irrigation zone.

The regulator should be installed upstream of the components requiring reduced pressure, while observing the indicated direction of water flow. The M Series is designed for both above-ground and below-ground installation.

Durable solution for irrigation systems

Rain Bird uses an engineering-grade plastic housing and stainless steel spring for the M Series. Its compact construction is specifically designed for pressure regulation within irrigation systems.

Different preset pressure levels within the PSI-M Series allow the regulator to be selected according to the requirements of each irrigation zone. The PSI-M-40 provides a nominal outlet pressure of 40 psi, corresponding to approximately 2.8 bar.

Technical data and specifications

• Manufacturer: Rain Bird
• Series: PSI-M
• Model: PSI-M40 / PSIM40
• Product type: Preset pressure regulator
• Outlet pressure: 2.8 bar
• Outlet pressure US: 40 psi
• Pressure setting: Factory preset
• Inlet: ¾" female thread
• Outlet: ¾" female thread
• Flow range: 0.5-2.27 m³/h
• Flow range: approx. 8.3-37.8 l/min
• Operating principle: Diaphragm operated
• Spring: Stainless steel
• Housing: Engineering-grade plastic
• Installation: Above or below ground
• Application: Irrigation systems requiring controlled operating pressure

Frequently asked questions about the PSI-M-40

What is the outlet pressure of the PSI-M-40?

The regulator is factory preset to 40 psi, corresponding to a nominal outlet pressure of approximately 2.8 bar.

Can the 2.8 bar pressure setting be adjusted?

No. The PSI-M-40 is a preset rather than an adjustable pressure regulator. If a different outlet pressure is required, an appropriately rated regulator should be selected.

When is a pressure regulator useful in an irrigation system?

A pressure regulator is useful when the available supply pressure exceeds the recommended operating pressure of downstream irrigation components. It allows the pressure supplied to an irrigation zone to be reduced to a more suitable level.

Does the PSI-M-40 require electricity?

No. The regulator operates mechanically and requires no electrical supply, batteries or connection to an irrigation controller.

What connections does the PSI-M-40 have?

The regulator has a ¾" female threaded connection at both the inlet and outlet.

Is 2.8 bar suitable for every drip irrigation system?

No. The required operating pressure depends on the drippers, dripline and other components used in the system. Their recommended pressure range should therefore be checked before selecting the regulator.