Technical Information Silicon differential pressure sensorApplication The differential pressure sensors USD70 are available for small measuring ranges with extremely high overload resistance. The differential pressure sensors USD70 with piezoresistive sensor and welded metal diaphragm are typically used in process and environmental industries. Applications are level, volume or mass measurement in liquids, differential pressure monitoring, e. g. of filters and pumps as well as flow measurement (volume or mass flow). Your benefits ■ Measuring ranges from 10 mbar (0.15 psi) and 30 mbar (0.45 psi) ■ Bridge output signal (mV/V) ■ High accuracy, repeatability and long-term stability ■ High overload resistance: ■ 316 L (stainless steel) version ■ Optional choice of diaphragm materials and filling oils People for Process Automation

Table of contents About this document . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 Document function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Symbols used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Function and input parameters . . . . . . . . . . . . . . . . . . .4 Measuring principle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Measured variable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Measuring range . . . . . . . . . . . . . . . . . . . . . ....

About this document Document function This document contains all the technical data for the device and provides an overview of the device versions that can be ordered. Symbols used Safety symbols

Measuring principle Metallic process diaphragm The metallic process diaphragms (4) are deflected on both sides by the applied pressures pi and p2. A filling liquid (3) transfers the pressure to one side of the measuring element, on which a resistance measuring bridge is located (semiconductor technology). The differential pressure-dependent change in the bridge output voltage is measured and put out. Measured variable Differential pressure Measuring range ► The measuring device must be operated only within the specified limits! ► The specified values are only achieved in the reference installation...

Output Output signal Uncompensated bridge output signal. Specifications valid at 0.5 mA supply current. Dynamic behaviorPerformance characteristics Reference operating ■ According to IEC 62828-2 conditions ■ Ambient temperature TA = constant, in the range 22 to 28 °C (72 to 82 °F) ■ Humidity j = constant, in the range: 5 to 80 % rH ± 5 % ■ Ambient pressure pU = constant, in the range: 860 to 1060 mbar (12.47 to 15.37 psi) ■ Position of measuring cell: horizontal ±1° ■ Measuring span based on zero point Measuring cell 10 mbar (0.15 psi)

* Data on static pressure influence refer to pressurization on both sides Long-term stability 1 year: ±0.20 % of URL 5 years: ±0.28% of URL 10 years: ±0.31 % of URL 15 years: ±0.34% of URL

Process temperature range -40 to 85 °C (-40 to 185 °F) Devices with inert oil: Minimum process and ambient temperature -20 °C (-4 °F) ► MWP (Maximum Working Pressure): This value refers to a reference temperature of 20°C (68 °F) and may be applied to the sensor for an unlimited time. Note the pressure-temperature dependence of the MWP. For pressure values permitted at higher temperatures, please refer to EN 1092-1: 2001 Tab. 18, ASME B 16.5a, JIS B 2220 (the current version of the standard applies). Deviating MXP specifications can be found in the relevant chapters of the technical information....

Weld seam overhang possible/ Schweißnahtüberhang möglich 37 ±0.01 (1.46) (max. 0.2) Materials in contact with process Diaphragm material: • Stainless steel AISI 316L (1.4435) • Alloy C276 (2.4819) Base body: • stainless steel AISI 316L (1.4404) Materials not in contact with process Measuring cell body: • Stainless steel AISI 316L (1.4404) Filling fluid: • Silicone oil • Inert oil – not suitable for temperatures below -20 °C (-4 °F) – For oxygen applications: see chapter "Pr

Current supplyElectrical connection Wiring diagram A0035256 1 Positive current supply 2 Positive output signal 3 Negative output signal 4 Negative current supply 5 Isolated potential housing 1 Positive current supply 2 Positive output signal 3 Negative output signal 4 Negative current supply Reference installation Reference installation according to installation instructions EA01484O. Endress+Hauser 9

Certificates and approvals RoHS The measuring system complies with the substance restrictions of the Restriction on Hazardous Substances Directive 2011/65/EU. Other standards and guidelines The applicable European guidelines and standards can be found in the relevant EU Declarations of Conformity. The following were also applied: DIN EN 60770 (IEC 60770): Transmitters for use in industrial process control systems Part 1: Methods for evaluating the performance of transmitters for control and regulation in industrial process control systems. DIN 16086: Procedure for writing specifications in data...

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