RAY FS is a Woltman volume measuring device with a built-in pulse transmitter to measure heat for billing hot water consumption (max. 120°C).
Its impeller axis is perpendicular to the pipe. It is particularly sensitive at low flowrates which increases the dynamic range of measurement.


  • MI004 approval in class 2 with a dynamic range of 25:1 (qp:qi)
  • Complete range from DN50 qp 15m3/h to DN150 qp 150m3/h
  • Remote transmission of quantities of flow (3m cable), compatible with calculators with pulse input
  • Horizontal installation only
  • Register can be rotated as required for easier reading
  • Very low pressure loss
  • Encapsulated and waterproof meter
  • As a safeguard against magnetic influences, a sealable antimagnetic screen is fitted on the meter
  • Temperature range: 15°C to 120°C
  • General
    Mounting positionHorizontal
    Medium temperature range°C15 ... 120
    Ambient temperature°C5 ... 55
    Ambient classE1 + M1
    Nominal pressurePNbar161
    Protection classIP 54
    ApprovalMID (DE-15-MI004-PTB010)
    1 special version on request
  • Technical data
    Nominal diameterDNmm506580100150
    Nominal flow rateqpm³/h15254060150
    Maximum flow rate (short-term)qsm³/h30305075187.5
    Minimum flow rateqil/h6001,0001,6002,4006,000
    Starting flow ratel/h606090901,000
    Pressure loss at qpΔpbar0.
    Pulse value reed switch 1l/pulse1001001001001,000
    Dynamic range 2 qp / qi25:125:125:125:125:1
    1 other pulse values on request
    2 other qp / qi on request
  • Display range
    Nominal diameterDNmm506580100150
    0.5 l ... 999,999 m³
    5.0 l ... 9,999,999 m³
  • Dimensions
    Nominal diameterDNmm506580100150
    Overall length (DIN 19625)Lmm270300300360500
    Overall length (DIN ISO 4064)Lmm300300350350500
    Flange diameterDmm165185200220285
    Hole circle diameterKmm125145160180240
    Number of screwholespcs44888
    Screwhole diameterD1mm1818181823
    Height (without counter extension)H1L155155190200400
    Height (with counter extension)H1mm195195230240440
    DiameterØ Bmm165185200220285
  • Pressure loss graph / Typical error graph

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