Netafim M Water Meter 1-1/2 in, Reed Switch 1.0 Gallon per Pulse (36M401.5T)

Netafim Water Meter for 1-1/2 in Supply Lines

Knowing how much water a block actually received is the first step to fixing uneven crops, runaway runoff or a quiet leak. This is the 1-1/2 in member of the Netafim 'M' series, item 70261-003230, model 36M401.5T. It has a corrosion-proof copper alloy body with male pipe thread ends. Inside, a multi-jet chamber spreads the flow evenly around a single impeller, which limits wear and holds calibration. That impeller is the only moving part in contact with water. A magnetic coupling drives the register through a sealed, stainless steel encapsulated housing, so the dial does not fog or collect moisture. The reed switch register closes once for every 1.0 gallon that passes, ready for a controller pulse input. Accuracy holds within ±2% from 3.5 GPM up to a maximum of 55 GPM, with 44 GPM as the nominal flow. Flows down to 0.9 GPM still register within ±5%. It is rated for 140 psi working pressure and liquids up to 122°F.

Installing a 1 1/2 Inch Water Meter on the Main

This meter is meant for main supply lines, ahead of the valves that split water into zones. Wired to an irrigation controller, its pulses let the system log gallons per cycle and flag a zone that suddenly draws more than usual. The same signal can feed a fertigation dosing system that injects by volume rather than by time. Flush the pipeline thoroughly before installing, so pipe shavings and grit never reach the impeller. There is no straight pipe requirement, which makes it easy to fit into a crowded header. Install it with the dial face horizontal and the flow arrow pointing downstream. The pipe must stay full of water whenever the meter is reading, so avoid high points where air collects. A continuous acting air vent upstream clears trapped air so the readings stay accurate. The register shows the running total in gallons, with pointers reading down to tenths of a gallon. Netafim backs this 1 1/2 inch water meter with three years on the metering components and five years on the body.

Key Features

• Reed switch register: Sends one dry-contact pulse per gallon to a controller, logger or dosing system.
• ±2% accuracy: Holds within 2% from 3.5 GPM up to the 55 GPM maximum.
• Multi-jet design: Spreads flow evenly on the impeller to limit wear and keep calibration.
• Sealed magnetic register: Stainless steel encapsulated dial that will not fog or take on moisture.
• Copper alloy body: Corrosion-proof body with male pipe thread connections.
• No straight pipe needed: Fits close to fittings and valves on a tight header.

Technical Specifications