HYDRUS 2.0 Composite



HYDRUS 2.0 is a static ultrasonic water meter designed for all applications of domestic cold water supply enabling accurate measuring with long-term stability under difficult conditions (no measurement of air and insensitive to sedimentation). Developed within the framework of the MID, it complies with the European regulations and holds sanitary conformity certificates (AoC DEU, ACS, WRAS and others). The integrated communication function supports meter data provision via mobile reading (walk-by/drive-by/passive drive-by) or fixed network (upgrade without on-site configuration). In combination with Diehl Metering’s IZAR fixed network system, which stands out with excellent coverage, high data granularity and timeliness will be maintained. This is what makes it a high responsive infrastructure to take actions immediately.
The meter offers integrated mioty® for Metering or LoRaWAN® for fixed network reading over private/public networks.


  • DN 15 to 50
  • MID approved with dynamic range up to R 800
  • IP 68 suitable for outdoor installations
  • Integrated radio communication based on Open Metering telegram
  • OMS over LoRaWAN® for fixed network with wM-Bus for mobile reading
  • mioty® for Metering for fixed network with wM-Bus for mobile reading
  • M-Bus/Pulse/Pulse, wM-Bus, wM-Bus along with L-Bus/Pulse
  • Display with error and alarm codes including leakage detection
  • Battery lifetime up to 16 years
  • U0 / D0, no need for calming sections
  • Privacy

    The HYDRUS 2.0 saves 1024 consumption values with a daily interval. This data can be read locally and accessed only by using the IZAR@MOBILE. As a second logging, a small amount of 32 consumption values can be stored. The HYDRUS 2.0 has a minimal sending interval of about 14 seconds and uses the OMS Generation 3 (not available with radio meters with C1 mobile mode or LoRaWAN®/C2) or 4, Profile B security level. Both, the radio protocol and the optical interface are encrypted by default.

  • Reach

    Information pursuant to Article 33 (1) of Regulation (EC) No 1907/2006 of the European Parliament and of the Council of 18 December 2006:
    This product series contains components with the following substances in a concentration of more than 0.1% weight by weight (w/w):
    - Lead titanium zirconium oxide (CAS no.: 12626-81-2)

  • General
    Medium temperature range°C+0.1 ... +90
    Ambient operating temperature°C-10 ... +55
    Ambient storage temperature°C-10 ... +70 (>35 °C max. 4 weeks)
    Nominal pressurePNbar16
    Power supplyTwo 3.6 VDC lithium batteries
    Battery lifetime T301/T501Up to 16 years
    Battery lifetime T701/T901Up to 16 years
    Communication interfacesOptical, OMS wM-Bus / Long range radio (R4, R4+, mioty® for Metering) 434 or 868 MHz, M-Bus, L-Bus and Pulse, LoRaWAN® 868 MHz
    Data storageFor errors, alarms and measuring values, data logging capabilities to record up to 1024 daily values +32 monthly values and two annual due dates
    Protection classIP 68
    1 Depends on the sending interval of the radio telegram, the telegram length and the ambient temperature at the installation
  • Technical data display
    Display indicationLCD, 9-digit, additional symbols/display counter/unit
    Units displayed DN 15Volume (m³ + 3 decimal places) and flow rate (m³/h + 3 decimal places)
    Values displayedDisplay test - volume - battery lifetime - firmware version - software checksum - flow - current/continuous/historical error - alarm status - high resolution volume - due date - due date volume - reverse volume - display counter - low battery indication - leakage indication - metrological log access - radio signal ON/OFF - alarm indication - billing value indication - and more display loop options to choose from
  • Interfaces - Overview
    OpticalFor switching the display loop and configuring / reading the meter via IZAR@MOBILE
    wMBus (R3)434 or 868 MHz, Open Metering radio as standard (R3) for mobile reading sent every 14 / 64 seconds (default)
    Long range radio R4 / R4+ / mioty® for Metering434 or 868 MHz, OMS for fixed network sent every 5 / 15 / 60 minutes
    LoRaWAN®868 MHz - OMS over LoRaWAN® for fixed network sent every 3 h / 5 h / 6 h (default) and OMS wM-Bus for mobile network sent every 64s (default); Complies to v1.0.3, certified to v1.0.2, Class A, supports Adaptive data rate (ADR)
    M-Bus2400 baud, cable length 1.5 m, power supply only via built-in battery - can be combined with two Pulse outputs
    L-BusIn combination with radio, cable length 1.5 m (only one interface communicating at the same time)
    Pulse (Open drain)Two Pulse outputs, or one Pulse and one L-Bus output, Pulse cable length 1.5 m
  • Security
    wM-Bus (R3), R4, R4+, mioty® for MeteringOMS Generation 3 or OMS Generation 4 Profile B, selectable
    LoRaWAN®Fixed Network uses internal LoRaWAN® transport encryption; Mobile Network uses OMS Generation 4 Profile B Individual keys
  • Volume / Pulse Open Drain
    Max. input voltageV30
    Max. input currentmA27
    Max. voltage drop at active outputV/mA2/27
    Max. current through inactive outputμA/V5/30
    Max. reverse voltage without destroying outputsV6 (in case current does not exceed 27 mA)
    Pulse ratesl/pulseDecadic 1 / 10 (depending on nominal diameter)
    Pulse output 1 variantsTotal volume or forward volume
    Pulse output 2 variantsFlow direction or error, reverse volume
    Pulse frequencyMax. frequency 10 Hz
    Pulse width50 - 125 ms
  • Possible communication interfaces
    wM-Bus/Pulse/L-Bus3 wire
    wM-Bus onlywithout wire
    R4 / R4+ / mioty® for Meteringwithout wire
    LoRaWAN® and OMS radiowithout wire
    M-Bus only2 wire
    M-Bus/Pulse/Pulse5 wire
    Pulse/Pulse3 wire
    IZAR BE PULSE4 wire
  • Technical data
    Nominal diameterDNmm15152020
    Permanent flow rateQ3m³/h1.62.52.54
    Overall lengthLmm110110190190
    Dynamic (Q3/Q1)R400800800800
    Overload flow rateQ4m³/h23.1253.1255
    Transitional flow rateQ2l/h6.4558
    Minimum flow rateQ1l/h43.133.135
    Starting flow ratel/h1.
    Pressure loss at Q3bar0.190.460.40.4
    Pressure loss at Q4bar0.30.720.630.63
    Maximum flow rate2Qhighm³/h2.84.374.377
    Flow rate at ΔP = 1 bar3.673.693.955.39
    2 Outlet pressure minimum 3 bar, maximum 100 hours per year, closed pipeline network
    3 Please see table DIMENSIONS
  • Approval
    ApprovalMID DE-19-MI001-PTB012
    Dynamic range (Q3/Q1)RUp to 800
    StandardsEN 4064, EN 14154, OIML R49
    Sanitary conformityAoC DEU, ACS, WRAS and others
    LoRaWAN® certification1.0.2
  • Dynamic range (R=Q3/Q1)
    Q3 1.6 m³/h - T30 / T50R400
    Q3 1.6 m³/h - T70 / T90R400H; 250V
    Q3 2.5 m³/h - T30 / T50R160; 800
    Q3 2.5 m³/h - T70 / T90R160; 400; 800H / 400 V
  • Dimensions
    Nominal diameterDNmm15152020
    Permanent flow rateQ3m³/h1.62.52.54
    Overall lengthLmm110110190190
    Counter lengthL1mm89898989
    Counter widthBmm89898989
    Overall length with couplingL2mm190190290290
    Connection thread on meterInchG¾BG¾BG1BG1B
    Connection thread of couplingInch
    Weight without coupling (approx.)kg0.
    Weight with coupling (approx.)kg0.
  • Pressure loss graph / Typical error graph