H250 M40


Catalog excerpts

H250 M40 - 1

Technical Datasheet Variable area flowmeter • • • • Secure, cost-effective measurement and display, even without power supply Modular, can be expanded right down to FOUNDATIONTM Fieldbus A device that meets all Ex requirements, worldwide Sturdy, closed design for high resistance to pressure, temperature and product

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H250 M40 - 3

1.1 Intelligent Modularity The H250 all-metal variable area flowmeters cover the entire range of requirements of the process industry. The modular device design and flexible production structure form the basis for application and customer-based device versions. The basis of the H250 M40 is its purely mechanical design. Additional electronic modules can be added or replaced at any time without interrupting the process. This way, the functionality of the device adapts to any changed requirements. From analogue flow measurement without auxiliary power to digital integration into a fieldbus...

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H250 M40 - 4

Simple, low-cost installation: Measurement and indication without auxiliary power supply Universal Ex concept: Ex i and Ex d Modular scalability – from mechanical to fieldbus Any installation position: vertical upward, horizontal, vertical downward 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 range: up to100:1 High application safety, even with extremely low flows...

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H250 M40 - 5

1.2 Options and variants Robust design for harsh process conditions The measuring principle allows for a robust, closed design without sensor integration, as the height of the float is transferred to the indicator by way of a magnetic coupling. This allows for high pressure versions that can withstand up to 900 barg / 13,000 psig. All wetted, pressurised parts are made as standard of 1.4404/316L stainless steel and meet the requirements of the NACE MR0175 standard. To guarantee the longevity of the device even with chemically harsh products, it is possible to use special materials such as...

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H250 M40 - 6

Versions for special installation positions Variable area flowmeters typically feature a vertically positioned measuring cone through which the medium flows from bottom to top, lifting a float against the weight. If the installation structure does not permit otherwise, versions for horizontal or inverted (from top to bottom) installation positions are used. The missing reset force of the variable area float weight is replaced by a spring. Version with extended measuring range 100:1 The normal measuring range of the H250 measuring device is 10:1. A measuring range of 100:1 can be achieved by...

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H250 M40 - 7

1.3 Functional principle The H250 flowmeter operates in accordance with the float measuring principle. The measuring unit consists of a metal cone in which a float can move freely up and down. The flow goes from bottom to top. The float changes position so that the lifting force acting on it F1 is in equilibrium with the form drag F2 and its weight F3: F3 = F1 + F2 1 Indication principle M40 magnetic coupling 2 Magnetic coupling sensors 1 For the indicator, the flow-dependent height of the float in the measuring unit is transmitted by means of a magnetic coupling and displayed on a scale. 2...

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H250 M40 - 8

2.1 Technical data • The following data is provided for general applications. If you require data that is more relevant to your specific application, please contact us or your local sales office. • Additional information (certificates, special tools, software,...) and complete product documentation can be downloaded free of charge from the website (Downloadcenter). Measuring system Application range Flow measurement of liquids, gases and vapours Function / Measuring principle Variable area measuring principle Measured value Primary measured value Float position Secondary measured value...

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H250 M40 - 9

Materials Device Stainless steel CrNi 1.4404 / 316L Hastelloy® C-22 (2.4602) solid or plated CrNi steel 1.4571 with TFM/PTFE 2 PTFE or Al2O3 with FFKM gasket Measurin Float g tube Float guide Ring orifice 1 DN100/4" only PTFE 2 TFM/PTFE liner (electrically non-conductive), conductive PTFE on request Other options on request. • Special materials: e.g. SMO 254/6Mo, Titan, Hastelloy® C276/2.4819, Monel / 2.4360 a.o. • Float damping: ceramic or PEEK • Standard gasket for devices with female thread as insert: O-Ring FPM / FKM, others optional e.g. FFKM, EPDM M40 Aluminium, single-layer powder...

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H250 M40 - 10

Minimum ambient temperatures Tamb. with electrical components Design Limit switches SJ3,5-SN / I7S23,5-N / Reed SPST 1 Display contrast out of the temperature range 0...60 °C / 32..140°F decreasing. Temperatures H250/M40 - with electrical components [°C] Tamb. < +40°C Version with Limit switch NAMUR Limit switch NAMUR Limit switch NAMUR Maximum product temperatures H250/M40 - with electrical components [°F] Tamb. < +104 °F Version with Limit switch NAMUR Limit switch NAMUR Limit switch NAMUR 1 if there are no heat insulation measures, a heat-resistant cable is necessary (continuous...

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H250 M40 - 11

High-Temperature version 2-wire current output 4…20 mA with HART 5 / HART 7 ESK4 with LCD, binary status outputs, digital counter and pulse output. FOUNDATION FIELDBUS interface Cable glands Cable gland Cable diameter Nickel-plated brass Stainless steel Limit switches K1/K2 Terminal connection Limit switches Switching element function Pointer vane not detected Pointer vane detected Continuous current Switching cycles 1 safety oriented 2 no inductances Current output ESK4 / ESK4A Terminal connection Power supply Min. power supply for HART Measuring signal 4.00...20.00 mA = 0...100% flow...

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H250 M40 - 12

ESK4 HART® configuration Manufacturer name (code) ® Model name / HART Revision Physical layer ESK4 / ESK4A process variable Values [%] from full scale range Over range Device error identification Multi-drop mode Communication standard H1 FOUNDATION Fieldbus protocol Power supply Nominal current Error current Boot-up current after 10 ms For more details see the supplementary instructions "H250 M40 Foundation Fieldbus" Communication standard Power supply Nominal current Error current Boot-up current after 10 ms For more details see the supplementary instructions "H250 M40 Profibus PA"

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