Water Meters

A water meter is the one instrument on a head end that tells you what the system actually did rather than what the schedule said. Growers fit one to prove water use to a permitting authority, to check that a block took the volume the controller was set for, or to catch a leak or a stuck valve before it shows in the crop.

The right type depends on your water source, your pipe size and whether the meter needs to talk to a controller. ML Irrigation supplies Netafim and Bermad meters, from ½" threaded multi-jets to 12" flanged turbines and electromagnetic meters. Ask us which one fits your site.

Which meter type fits your water source and pipe size?

Start with the water. On clean well or municipal water a mechanical meter is the usual choice. Netafim's M Series Water Meters, which Netafim call the industry's smallest water meters, and Bermad's Bar Meter Multi-Jet, threaded from ½" to 2", cover small supply lines and individual houses. Multi-jet spreads the load evenly around the impeller, which cuts wear and keeps the meter accurate for longer.

On pond, surface or reclaimed water that carries debris, the measuring element has to be out of the way of it. Netafim's WMR axial turbine lets foreign matter pass straight through, and Bermad's Turbo-IR paddle wheel sits out of the main stream so suspended matter barely touches it. Either suits water that would foul a full-bore turbine.

For mainlines from 3" up, the choice is between a turbine and a meter with no moving parts. Netafim's WST turbine runs 3" to 12" and Bermad's flanged Turbo-Bar Woltman 1½" to 12". Where the meter must read accurately at low flows, or nothing can be allowed to wear, look at Bermad's electromagnetic range, with the M10 and MUT7000 in 2" to 6", or Netafim's Octave Ultrasonic, which spans under 1 gpm to 5,500 gpm at ±1.5% and ships with its own accuracy certificate for a water authority.

Fertigation lines get their own meter. Netafim's Fertilizer Meters are corrosion-resistant, light enough for an injection line, with a sealed register that does not fog in a fertigation shed.

What does the meter need from the pipe, the power and the controller?

Every mechanical meter wants a settled flow profile, meaning straight pipe on both sides. A meter fitted hard against an elbow or a valve reads wrong no matter how good it is. Netafim's WST turbines in 3" to 8" have built-in straightening vanes that cut the requirement to 5 diameters upstream and 2 downstream instead of the usual 10, often the difference between fitting a meter in an existing pump house and not. Where there is no straight run at all, Bermad's MUT1000 wafer electromagnetic clamps between flanges without a pipe run of its own.

Decide up front whether the meter is a dial you read or a signal a controller counts. Netafim's M Series and WST and Bermad's Turbo-Bar and Turbo-IR all offer pulse outputs, and the WST adds photo diode outputs. Pulse values differ by model and pipe size, so match the meter's pulse value to what the controller expects before you order.

Electromagnetic meters need power. Bermad's M10 is the meter they pair with their Omega controllers, the MUT1000 is DC-powered, and the MUT7000 carries its own battery-powered converter so it can sit at a remote hydrant with no mains supply. The MUT1222, MUT2200 and MUT2300 each come with an MC406 or MC608 converter, which sets the readout and output.

Match the body to the pipe: threaded on the Bar Meter, grooved on the M10, flanged on the Turbo-Bar and Turbo-IR, wafer on the MUT1000.

What goes wrong, and how the Netafim and Bermad lines differ

The mistakes we see repeat every season. A meter sized to the pipe rather than the flow, so it under-reads on small flows; this is where Bermad's M10 and MUT7000 earn their place, since they hold accuracy at low flow rates where a mechanical meter under-reads. A full-bore turbine on pond water, which fouls. A meter fitted without the straight pipe it needs. A register that fogs in a humid fertigation shed, which is why Netafim seal the Fertilizer Meters' register and Bermad seal the Turbo-Bar's magnetic register from the water. And a pulse output wired to a controller expecting a different pulse value, so every total is off by a fixed factor. Filter upstream of any mechanical meter; a meter is not a strainer.

The two lines come at metering from different ends. Netafim's range grows out of the head end of a drip system: compact multi-jets, a turbine that passes debris, a turbine that fits a tight pump house, an ultrasonic with a certificate, and a dedicated fertilizer meter. Bermad are the control-valve specialists. The IR-900 and IR-910 hydrometers put meter and valve body in one unit, and the IR-910 adds a solenoid so a hydrant meters the water and switches the zone from the same body, replacing a meter, a valve and the fittings between them. If the meter is only a meter, either line will do. If it is one piece of an automated block, start with Bermad.