SYElectromagnetic Water Meters

SY Photo


Measurement feature Accurate measurement of small flowrate
Measurement range 1:1000
Measurable water City water, plant water, agricultural water *1
Meter connection method Flange(JWWA standard) type
Body material Cast stainless steel
Flow path Cone structure

Enhanced Durability! Lnnovative water meter for the new-era

As consumption of water has increased in the recent years, an advanced water meter has been desired for the use of long time and stable high accuracy measurement with trouble-free operation. Responding to these needs, Aichi has conducted proprietary research over and over and has succeeded in developing the world′s first electromagnetic water meter “SU Series” and “SY Series” that provides 8 years of non-stop service with built-in battery. These water meters for the new-era are suitable for water control with innovative enhanced durability that expands the world of measurement.

Outstanding features that expand the world of measurement

Outstanding durability with no moving parts

Since there are no rotating or sliding parts such as vane wheel or indication gears, troubles caused by wear of moving parts and intrusion of foreign substances are eliminated. Therefore, stable measuring accuracy can be maintained over a long period of time.

High accuracy measurement whether large continuous or small flowrates

The SU Series has almost no head pressure loss at maximum flowrate measurement, it is suitable for measuring flowrates of large continuous water supply and distribution. The SY Series is capable of measuring small flowrates with high accuracy owing to its special structure.

Wider measurement range

The measurement range is as wide as 1:200 for the SU Series, and 1:1000 for the SY Series. High-accurate measurement from very small (min. accurate flowrate) to large (max. flowrate) flowrates is possible.

8 years of continuous operation with a built-in battery

The power consumption has been reduced to 1/1000 (according to Aichi’s comparison data) from the conventional general electromagnetic flowmeter, and with a built-in lithium battery applied, 8 years of continuous measurement is realized. Consequently, there is no need of maintenance during this period.

Constant display on easy-to-read LCD

Bright and large LCD have been incorporated for the digital display of integrated flow and instantaneous flowrate values of all times. By utilizing such instantaneous flowrate value, flowrate adjustment of water supply and distribution can be easily performed.

Free installation position allows installation anywhere

Having no mechanical moving parts, the meter can be installed on a horizontal, vertical or inclined position, allowing installation anywhere with very little restriction for its location.

All stainless steel body with outstanding durability

Both the compact design wafer type (SU)* and easy-to-install flange type (SY) are made of all stainless steel body having the feature of long life. *The SU with 250, 300 and 350mm nominal diameters are flange types.

Flexible corresponding to various systems of specific use

Since these meters are equipped with electronic statement signal output function, installation of transmitter for specific use will enable flexible corresponding to various systems such as remote meter reading, automatic meter reading, as well as monitoring and controlling.


Nominal diameter 50 75 100 150
Flow-rate range Max. flow-rate (2qp)(m3/h) 40 90 160 300
Standard flow-rate (qp)(m3/h) 20 45 80 150
Transitional flow-rate (qt)(m3/h) 4 9 16 30
Min. flow-rate (qmin)(m3/h) 0.6 1.35 2.4 4.5
Min. accurate flow-rate (qc)(m3/h) 0.04 0.09 0.16 0.3
Measurement starting flow-rate (qs)(m3/h) 0.01 0.0225 0.04 0.075
The meter does not measure a flowrate less than the measurement starting flowrate (qs). The qs to qmin flowrate range is not within the calibration tolerance.
Max. limit flow-rate (qL)(m3/h) 60 120 200 400
The 2qp to qL flowrate region is not within the calibration tolerance.
Pressure drop at max. flow-rate (MPa) 0.041 0.039 0.035 0.032
Working pressure (MPa) 0.75 (Approx. 7.5kgf/cm2)
Display Integrating flow (m3) 999999.9999 9999999.999
Instantaneous flow-rate (m3/h) 99.99 999.9
Meter weight (kg)10121625 10 12 16 25


Display No-water warning mark mark1 mark lights
Low-battery alarm mark mark2 mark flickers
Measurement stop alarm mark mark3 mark lights
Measured fluid Suitable working temperature (°C) 0 to +30
Fluid conductivity rate (μs/cm) 50 or more
Power supply and battery life Lithium battery (Nominal 3.6V), battery life approx. 8 years (At average environmental temperature of 20°C)
Environmental temperature range (°C) -10 to +55 (The battery life is shortened at higher temperature.)
Waterproof structure JIS C0920 (Underwater use), continuous use at 1m water depth is possible
Piping method Flange (JWWA standard) type
Meter installation position Free (Horizontal, vertical and inclined installation are possible.)
External output SY-FN type No external output functions (Only field display)
SY-FC type Electronic statement signal for exclusive independent receiver (SR-4 type) Transmitter: MX35 type
SY-FM type Open drain unit pulse signal Transmitter: MX39 type
SY-FL type 8-bit electronic statement signal (The signal widely diffused in Japan for water and gas meters), open drain unit pulse signal Transmitter: MX38 type




Head Loss




Transmitter specifications MX Series


MX35 type

Signal Electronic statement signals for exclusive independent receiver (SR-2 type)
Number of wires 2
Transmitting distance 50m with standard cable
Life Approx. 10 years


MX39 type

Signal Open drain unit pulse
Pulse ON time 100±10ms
Pulse unit 100L/P or 1m3/P (10m3/p·special specification)
Number of wires 2
Transmitting distance 200m with standard cable
Life Approx. 10 years



MX38 type

Signal 1) Ver. 2.6A Only 8-bit electronic statement 2) Ver. 2.6A 8-bit electronic statement and open drain unit pulse
Number of wires 2 wires for 1), 4 wires for 2)
Transmitting distance 200m with standard cable (When connected with independent type receiver QA8D-1R)
Life Approx. 8 years (Differs according to number of readings)



Specifications may vary by country, about which please confirm at the time of inquiry.

・Specifications are subject to change without notice.
Product Warranties