Minute flow rate measuring and transmitting with flameproof

MA-920 Series Intelligent, Pure Electronics Micro Flowmeter

MA-920 MICRO FLOWMETER is a metal tube variable area flow meter which has local indication with transmitting of minute flow rate of liquids and gases.
TOKYO KEISO's long time production know-how and recent electronics technology have been successfully combined.
The existing micro flow meters generally need a signal linearizer due to mechanical problem of very minute sensing part.
In MA-920, integrated microprocessor takes care of these automatic compensation based on individual stored calibration data and achieves high accuracy even for small flow rate.
The 4 to 20 mA with 2-wire system makes field wiring easier.

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Specifications are subject to change without prior notice.


·  Covers very low flow rates of 0.6 to 3 L/h
·  2-wire 4 to 20 mA DC output
·  Magnetic field sensor detects the float movement with electronics to eliminate hysteresis.
High accuracy and repeatability have been achieved
· Easy- to- read digital LED display
· No liquid dampers are needed even for gas measurement applications
·  Ex d IIC T6 flame proof construction suitable even for Hydrogen atmosphere


Measuring fluid Liquids and Gases
Viscosity limit for liquid flow measurement (Free from solids and particles)
Meter size 1/2 Viscosity (Max.) 2.0mPa・s
Meter size 3/4、1 Viscosity (Max.) 5.0mPa・s
Measureing range Liquid (Water)      Measuring range is subject to liquid viscosity.
Min. 0.6 to 3 L/h                     Max. 60 to 600 L/h
Gas (Air, 0°C, 1atm)
Min. 10 to 100 L/h(nor)        Max. 2.2 to 22 m3/h(nor)
Fluid temperature 0 - 120℃
Fluid pressure Max. 2.94MPa
High pressure type19.6MPa          Material of high pressure type is SUS 316.
Allowable pressure is subject to the flange rating when the connection is flange type.
Material Body: SCS14
Tapered tube: SUS316
Float: SUS316
PPS resin / Titanium will be used for 1/2" meter size, and PPS resin / SUS316 will be used for 3/4 and 1" meter sizes in gas measurement applications.
Process connection Screw (1/4, 3/8, 1/2, 3/4 or 1")
JIS10KFF flange (10A, 15A, 20A, or 25A)
Opt. NPT or other screw
       Other flanges than JIS10KFF
(Indication and output)
10 L/h or more of F.S. (water) ±2%F.S.
Less than 10 L/h of F.S. (water) ±3%F.S.
100 L/h (nor) or more of F.S. (air) ±2%F.S.
Range ability 10:1 (Accuracy guranteed range)
   Range ability of the meter with the full scale range smaller than 5L/min (water)is 10:2.
   It may differ depending on the liquid viscosity.
Output signal 4 to 20 mA DC (2-wire system)
Allowable load resistance: 600Ω or less (at 24 V DC, including wiring resistance)
(500Ω or less for ATEX-certified)
Power source 24 V DC ±10% (Operating voltage range : 12 to 33 V DC)
Indication Upper (main display): Four digits for measurements and error codes
Lower (sub display): Five digits for supplementary information
Enclosure Flameproof
Ex d IIC T6 (TIIS-certified)
Ex d IIC T6 Gb (NEPSI-certified)
Ex d IIC T6 (KOSHA-certified)
II 2 G Ex d IIC T6...T4/
II 2 D Ex tD A21 IP65 T85°C (ATEX-certified)


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