Forbes Marshall - Trusted Partners in Steam Engineering & Control Instrumentation
This is a product of KROHNE Marshall.

H250 M40

The H250 M40 is the standard variable area (VA) flowmeter for the process and OEM industry. The VA meter combines mechanical flow measurement of liquids or gases with state-of-the-art communication capabilities. The device is modularly extendable. Additional electronic modules can be added or replaced at any time without process interruption. In this way, its functionality adapts to new requirements – from analogue flow measurement without auxiliary power to digital integration into a fieldbus system.

The H250 M40 is available in various materials and in many different versions. The sturdy all-metal flowmeter can be also used in applications with high pressures (up to 1000 barg / 14500 psig), temperatures (-196…+400°C / -320…+752°F) or aggressive media. It even allows installation in horizontal or fall pipes up to DN150 / 6″. A special version for use in hygienic applications is also available. The H250 M40 is intrinsically safe and explosion-proof. Certain variants of the flowmeter with limit switch or analogue output are suitable for use in Safety Instrumented Systems (SIS). Electronic device diagnostics and additional application diagnostics are available to increase application reliability, e.g. the detection of a float blockage due to impurities or pressure surges and the reporting of pulsating flow or gas compression oscillations of the float.

Product features and options depend on device configuration: Contact us to make sure that your preferred functionality can be combined in one device.

  • Simple, low-cost installation: able to measure and display without auxiliary power supply
  • Unique modularity and serviceability: Limit switches, 2-wire 4…20mA, totalizer with LCD and pulse output, fieldbus interfaces
  • NE 107 device and application diagnostics with CFM (Continuous Float Monitoring), e.g. for float blockade detection
  • Universal ex-concept: Explosion proof and intrinsically safe
  • Various stainless steel and alloy sensor materials
  • Optional stainless steel housing for corrosive atmospheres
  • Ingress protection IP66 and IP68 / NEMA4X and NEMA6, IP69K optional
  • Full scale value for liquids: 10…120,000 l/h / 5…32,000 GPH
  • Full scale value for gases: 0.7…2800 m3/h / 25…100,000 SCFH
  • Turndown ratio 10:1 (optional 100:1)
  • Maximum measuring error: ±1.6% (acc. to VDI/VDE 3513-2) or ±1.5% of full scale
  • Suitable for use in Safety Instrumented Systems with SIL 2, in redundant design (1oo2) also in SIL 3 applications (type A device)
  • Optional hygienic design for use in the food and pharmaceutical industry
• Robust measuring tube construction for high process temperatures and extreme operating pressures
• Choice of material: Stainless steel, hastelloy®, titanium, Monel, PTFE/TFM etc.
• Many connection variants: flanged, screwed, clamped, weld-on ends etc.
• Extended measuring span: up to 100 : 1
• High application safety, even with extremely low flows
• Nitrogen inerting to avoid explosive atmospheres
• Measurement of additives such as catalysts,tensides, anti foaming and anti-corrosion agents
• Measurement of chlorine, sulphur and ethylene compounds
• Measurement of distilled or demineralised water

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