• Certified to NSF/ANSI 61
  • Dry top multi-jet design
  • Size / flow ranges:
    • 3/4 inch: 0.25 to 20 GPM
    • 1 inch: 0.75 to 50 GPM
    • 1 1/2 inch: 1.5 to 100 GPM
    • 2 inch: 2 to 160 GPM
  • ±1.5% of reading accuracy
  • 105°F (40°C) max temperature
  • Sensor types:
    • Hall-effect device
    • Reed switch
    • Totalizer only
  • Tolerates low quality water
  • Pressure: 150 psi operating


The Seametrics MJN Series Pulse Water Meters use the multi-jet principle, which has been an internationally-accepted standard for many years. This type of meter is known for its wide range, simplicity, and accuracy in low quality water. The MJN Series are certified to NSF/ANSI 61. The impeller is centered in a ring of jets, with inlet jets on one level and outlet jets on another. A gear train drives the register totalizer dials. For pulse output, one of the pointers is replaced by a magnet, which is detected by an encapsulated sensor attached to the outside of the lens. Pulse rate is determined by the dial on which the magnet is placed, and by the number of sensors (single or double).

Changing the pulse rate requires no special tools and can be done in the field. Mechanically, all MJN-Series meters are the same. The MJN Series has a brass body and is available in 3/4", 1", 1 1/2" and 2" versions. The MJNE meters use a solid-state, long-lasting Hall-effect sensor, which requires power. It is suited for use with Seametrics controls and metering pumps that have sensor power. The MJNR meters use a two-wire reed switch. They provide a dry contact closure and do not require power. The MJNT meters totalize only and do not have a sensor.


This product can be used in the following applications:

Here's how some of our customers use this product...

Monitoring Domestic Water Usage

The Background: Our customer is a homeowner living in an area where water usage is regulated. He wants to be able to monitor the amount used for personal consumption.

The Problem: The customer requires an economical, compact flow meter with no straight run requirements, the ability to measure in gpm, and at least ±15% accuracy.

The Solution: We suggested the Seametrics MJ series turbine meter which meets all the customer's needs with regard to size and cost, as well as delivering an accuracy within ±1.5% of the reading.

Simple Water Metering in a Remote Location

The Background: The customer has a remote cabin and wants to measure the amount of water he pulls from a local water source.

The Problem: The customer wants a cost effective solution that can handle the rugged, remote location and does not rely on electrical power, as none is available onsite.

The Solution: The Seametrics MJ Series provided everything the customer needed. It is a rugged and reliable meter at a great price point. It is available with a mechanical totalizer ideal for off-grid locations and the wide turndown ratio works well with low flow applications

In Stock

Part Number Sensor Type Size Pulse Rate Price Available
Reed switch dry contact
3/4 inch (0.22 to 22gpm)
1 gallon per pulse
$235.00 3 in stock
Mechanical register only
3/4 inch (0.22 to 22gpm)
No pulse output with totalizer
$228.00 1 in stock

Interested in Other Part Numbers?

Other part numbers are available to order but are not currently in stock. Current availability for non-stock parts is "Usually ships in 2-3 weeks". Click here to select options