Produkty dla instrumenty (933)

ConduSense Platinum - Komórki Przewodności - Komórki Przewodności do Precyzyjnych Pomiary

ConduSense Platinum - Komórki Przewodności - Komórki Przewodności do Precyzyjnych Pomiary

Die ConduSense Platinum Leitfähigkeitszellen von Vuille pH-Elektroden AG bieten höchste Präzision und Zuverlässigkeit bei Leitfähigkeitsmessungen. Speziell konzipiert aus hochwertigem Platin, ermöglichen diese Zellen mit Zellkonstanten genaue Messungen in einer Vielzahl von Anwendungen, von industriellen Prozessen bis hin zur Überwachung von Wasserqualität. Eigenschaften: Hochpräzise Leitfähigkeitsmessungen: Die ConduSense Platinum Leitfähigkeitszellen gewährleisten genaue und zuverlässige Messungen in einem breiten Leitfähigkeitsbereich. Die Verwendung von Platin als Messelement sorgt für eine präzise Erfassung von elektrischer Leitfähigkeit. Vielseitige Anwendungen: Diese Leitfähigkeitszellen sind vielseitig einsetzbar und eignen sich ideal für Anwendungen in verschiedenen Branchen, darunter industrielle Prozesskontrolle, Wasseraufbereitung und Laboranwendungen.
Elektrody Redox - Elektrody pH/Redox, Elektrody Redox z platyną lub złotem jako elektrodą pomiarową

Elektrody Redox - Elektrody pH/Redox, Elektrody Redox z platyną lub złotem jako elektrodą pomiarową

Die Schnelle Kombi-pH-Elektrode mit Temperatursensor von Vuille pH-Elektroden AG definiert Effizienz neu, um präzise pH-Werte in wässrigen und teilwässrigen Medien zu bestimmen. Durch die innovative Integration eines Temperatursensors unterhalb der pH-Glas-Membran setzt diese Elektrode neue Maßstäbe in puncto Geschwindigkeit und Genauigkeit. Eigenschaften: Schnelle Temperaturkonstanz: Der Temperatursensor befindet sich an der äußersten Spitze der Elektrode, was eine schnelle und präzise Erfassung der Messflüssigkeitstemperatur ermöglicht. Breiter Temperaturbereich: Geeignet für Temperaturen zwischen –30 und 135 °C, was vielfältige Anwendungsbereiche abdeckt. Verkürzte Wartezeiten: Die Elektrode verkürzt die Wartezeiten bis zur Temperaturkonstanz um etwa 40%, optimiert für effiziente Serienmessungen.
Elektroda Redox SpaShield - Maksymalne Bezpieczeństwo Dezynfekcji dla Twojego Jacuzzi

Elektroda Redox SpaShield - Maksymalne Bezpieczeństwo Dezynfekcji dla Twojego Jacuzzi

Die SpaShield Redox-Elektrode von Vuille pH-Elektroden AG wurde speziell entwickelt, um die Desinfektionssicherheit in Ihrem Whirlpool zu maximieren. Diese hochmoderne Redox-Elektrode garantiert eine präzise Überwachung des Redox-Potentials und sorgt so für hygienisch einwandfreies Wasser in Ihrem Whirlpool. Eigenschaften: Effektive Desinfektion: Die SpaShield Redox-Elektrode ermöglicht eine effektive Überwachung des Redox-Potentials, was entscheidend für eine wirksame Desinfektion Ihres Whirlpoolwassers ist. Dies gewährleistet maximale Hygiene und Sicherheit. Langlebige Konstruktion: Der Kunststoffschaft und das spezielle Design machen die Redox-Elektrode äußerst langlebig und widerstandsfähig gegenüber den Bedingungen in Whirlpools. Sie bleibt selbst unter anspruchsvollen Bedingungen leistungsfähig.
Precyzyjne Elektrody Selektywne Jonów (ISE) - Elektrody, selektywne dla jonów (ISE), specyficzne dla jonów lub wrażliwe na jony elektrody

Precyzyjne Elektrody Selektywne Jonów (ISE) - Elektrody, selektywne dla jonów (ISE), specyficzne dla jonów lub wrażliwe na jony elektrody

Die ionenselektiven Elektroden (ISE) von Vuille pH-Elektroden AG repräsentieren die Spitze der Technologie für die genaue Erfassung spezifischer Ionen in verschiedenen Anwendungen. Entwickelt für Labore, industrielle Prozesse und Forschungseinrichtungen bieten unsere ISE-Produkte unübertroffene Präzision und Zuverlässigkeit. Eigenschaften: Spezifische Ionenerkennung: Unsere ISEs ermöglichen die selektive Erfassung einzelner Ionen, was besonders in analytischen Anwendungen von entscheidender Bedeutung ist. Präzise Messungen sind für genaue Analysen und Forschungsarbeiten unerlässlich. Vielseitige Anwendungsbereiche: Von Laboren über industrielle Prozesse bis hin zu Umweltüberwachungssystemen bieten unsere ISEs vielseitige Einsatzmöglichkeiten. Sie sind für eine breite Palette von Ionenkalibrierungen und Messungen konzipiert.
Wysokoprecyzyjne Sensory Elektrochemiczne - Zaprojektowane do Szerokiego Zakresu Zastosowań

Wysokoprecyzyjne Sensory Elektrochemiczne - Zaprojektowane do Szerokiego Zakresu Zastosowań

Die hochpräzisen elektrochemischen Sensoren von Vuille pH-Elektroden AG setzen einen neuen Standard für Präzision und Zuverlässigkeit. Entwickelt für eine breite Palette von Anwendungen in den Märkten Chemie, pharmazeutische Industrie, Biotechnologie, Lebensmittel (Fleisch, Käse, Obst und Gemüse) und Getränke, Schwimmbad, Aquarium sowie Abwasser, bieten unsere Sensoren erstklassige Leistung in verschiedenen Umgebungen. Eigenschaften: Branchenübergreifende Anwendungen: Vuille pH-Elektroden AG produziert Sensoren, die sich nahtlos in verschiedene Branchen integrieren lassen. Von Laboren über industrielle Prozesse bis hin zur Lebensmittelindustrie decken unsere Sensoren ein breites Anwendungsspektrum ab. Innovative Technologie: Als innovatives Unternehmen verfolgen wir stets technologische Trends und setzen sie in unseren Sensoren um. Die Integration modernster Technologien ermöglicht eine schnelle Ansprechzeit und reproduzierbare Messungen.
Seria 21Y - Nadajniki ciśnienia

Seria 21Y - Nadajniki ciśnienia

The pressure transmitters of the 21Y series have no internal seal and a high insulation voltage of 300 VDC, and are extremely resistant to environmental influences. The sophisticated compensation circuit makes it possible to specify a narrow total error band. A wide range of pressure connections and electrical connections are available to choose from. Pressure Ranges:0…2 to 0…1000 bar Accuracy:±0,5 %FS Total Error Band:±1,5 %FS @ -10…80 °C Interfaces:4…20 mA, 0…10V Temperature Range:-40…100°C
Seria 22-PS - Nadajniki ciśnienia

Seria 22-PS - Nadajniki ciśnienia

The programmable pressure switches of the 22-PS series are encased in a compact yet robust steel housing and are available with PNP or NPN wiring. The pressure switches can be supplied pre-configured at the customer's request. With the aid of the dV22-PP programming unit (available for purchase separately), the two switch outputs can be programmed at any time to be normally closed or normally open at a range of switching points with a window or hysteresis function. Pressure Ranges:0…4 to 0…400 bar Total Error Band:±2,0 %FS @ 0…80 °C Interfaces:0,5…4,5 V, 2 switch outputs Special characteristics:Programmable pressure switch Homologation:none
Seria 35X - Nadajniki ciśnienia

Seria 35X - Nadajniki ciśnienia

The front-flush pressure transmitters of the 35X series use digital compensation with a mathematical model to achieve exceptional accuracy of 0,05 %FS – in the temperature range from 10 to 40 °C, this value even corresponds to the total error band. In addition to the digital RS485 interface, the X-line transmitters have a rangeable, analog current or voltage output. Pressure Ranges:0…0,3 to 0…1000 bar Accuracy:±0,05 %FS Total Error Band:±0,1 %FS @ -10…80 °C Interfaces:RS485, 4…20 mA, 0…10 V Temperature Range:-40…120 °C
Seria 33X - Nadajniki ciśnienia

Seria 33X - Nadajniki ciśnienia

The pressure transmitters of the 33X series use digital compensation with a mathematical model to achieve exceptional accuracy of 0,05 %FS – in the temperature range from 10 to 40 °C, this value even corresponds to the total error band. Additional measurements and selections can optionally be used to achieve a precision (and also, if calibrated in an accredited test laboratory, an accuracy) of 0,01 %FS. In addition to the digital RS485 interface, the X-line transmitters have a rangeable, analog current or voltage output. Pressure Ranges:0…0,3 to 0…1000 bar Accuracy:±0,05 %FS Total Error Band:±0,1 %FS @ -10…80 °C Interfaces:RS485, 4…20 mA, 0…10 V Temperature Range:-40…120 °C
Seria 7LD - Nadajniki ciśnienia

Seria 7LD - Nadajniki ciśnienia

The pressure transmitters of the 7LD series use the chip-in-oil technology developed by KELLER, uniting a pressure measuring cell, digital temperature compensation and signal processing in a compact housing made of stainless steel or Hastelloy. The transmitters are extremely resistant to environmental influences and delivery highly accurate measurement results as a digital output signal. The I2C interface and the low supply voltages make it easy to integrate in microcontroller-based systems. The extremely low power consumption is ideal for battery-operated devices. The D line is perfect for IoT solutions. Pressure Ranges:0…3 to 0…200 bar Accuracy:±0,15 %FS Total Error Band:±0,7 %FS @ -10…80 °C Interfaces:I2C Dimensions:⌀ 15 mm x 5 mm
Elektrody pH, z plastikowym trzonkiem - Elektrody pH do akwarium, stawu ogrodowego, gleby ogrodowej

Elektrody pH, z plastikowym trzonkiem - Elektrody pH do akwarium, stawu ogrodowego, gleby ogrodowej

Das AquaPrecision pH-Messsystem von Vuille pH-Elektroden AG bietet die ideale Lösung für genaue pH-Kontrollen in Aquarien, Gartenteichen und bei der Pflege von Gartenböden. Das System umfasst eine pH-Elektrode mit Kunststoffschaft, die speziell für diese Anwendungen entwickelt wurde, sowie ein hochpräzises pH-Meter. Eigenschaften: Speziell für Aquaristik und Gartenpflege: Die pH-Elektrode mit Kunststoffschaft ist optimal für den Einsatz in Aquarien, Gartenteichen und bei der Überwachung von Gartenböden geeignet. Sie liefert zuverlässige Messergebnisse für eine präzise pH-Kontrolle. Robuste Kunststoffkonstruktion: Der Kunststoffschaft der Elektrode ist robust und widerstandsfähig gegenüber den spezifischen Bedingungen in Aquarien, Gartenteichen und Gartenböden. Dies gewährleistet eine lange Lebensdauer und zuverlässige Leistung.
Seria 6L - Czujniki ciśnienia

Seria 6L - Czujniki ciśnienia

The pressure transducers of the 6L series have a small and compact design, making them ideally suited to OEM applications with limited installation space. The metal diaphragm is welded on front-flush and gap-free, separating off the piezoresistive pressure sensor, which is made of silicon, from the measuring medium. Every pressure transducer is measured over the entire pressure and temperature profile and is supplied with a detailed calibration sheet. Pressure Ranges:0…10 to 0…200 bar Accuracy:±0,5 %FS Long Term Stability:±0,35 %FS Dimensions:⌀ 13 mm x 4,5 mm Temperature Range:-10…80 °C
Seria 4L - Czujniki ciśnienia

Seria 4L - Czujniki ciśnienia

The pressure transducers of the 4L series are piezoresistive pressure sensors, isolated encapsulated in oil-filled metal housings. The flush separating membrane is laser welded without gaps. Each pressure transducer is measured via pressure and temperature and delivered with a detailed calibration sheet. Pressure Ranges:0…10 to 0…200 bar Accuracy:±0,5 %FS Long Term Stability:±0,5 %FS Dimensions:⌀ 11 mm x 4,2 mm Temperature Range:-10…80 °C
Seria 8L - Czujniki ciśnienia

Seria 8L - Czujniki ciśnienia

The pressure transducers of the 8L series have a compact, robust housing made of stainless steel, giving them excellent long-term stability for a range of OEM applications. The metal diaphragm is welded on front-flush and gap-free, separating off the piezoresistive pressure sensor, which is made of silicon, from the measuring medium. Every pressure transducer is measured over the entire pressure and temperature profile and is supplied with a detailed calibration sheet. Pressure Ranges:0…0,2 to 0…200 bar Accuracy:±0,5 %FS Long Term Stability:±0,2 %FS Dimensions:⌀ 17 mm x 7 mm Temperature Range:-40…125 °C
Seria 23 - Nadajniki ciśnienia

Seria 23 - Nadajniki ciśnienia

The series 23 pressure transmitters are designed for industrial applications and are based on the highly stable pressure transducers of the 10L series and a fully analog circuit. Thanks to its modular concept, this series can be flexibly adapted to customer-specific pressure connections and connector plugs. Pressure Ranges:0…0,2 to 0…1000 bar Accuracy:±0,5 %FS Total Error Band:±4,0 %FS @ -10…80 °C Interfaces:4…20 mA, 0…10 V Temperature Range:-40…100 °C Pressure-resistant encapsulation:Serie 23Ed
Seria 7LHPD - Nadajniki ciśnienia

Seria 7LHPD - Nadajniki ciśnienia

The pressure transmitters of the 7LHPD series for high pressure applications use the chip-in-oil technology developed by KELLER, uniting a pressure measuring cell, digital temperature compensation and signal processing in a compact housing made of stainless steel or Inconel. The transmitters are extremely resistant to environmental influences and delivery highly accurate measurement results as a digital output signal. The I2C interface and the low supply voltages make it easy to integrate in microcontroller-based systems. The extremely low power consumption is ideal for battery-operated devices. The D line is perfect for IoT solutions. Pressure Ranges:0…400 to 0…1000 bar Accuracy:±0,15 %FS Total Error Band:±1,0 %FS @ -10…80 °C Interfaces:I2C Dimensions:⌀ 15 mm x 8 mm Intrinsic safety:Series 7LDEi
Seria PD-33X - Czujniki ciśnienia

Seria PD-33X - Czujniki ciśnienia

The differential pressure transmitters of the PD-33X series are suitable for 'wet/wet' applications. They have a single silicon diaphragm in their interior, which is pressurised from both sides and measures the pressure difference directly. This design enables them to measure small pressure differences even at an extremely high line pressure. The transmitters use digital compensation with a mathematical model to achieve exceptional accuracy of 0,05 %FS – in the temperature range from 10 to 40 °C, this value even corresponds to the total error band. Pressure Ranges:0…3 to 0…30 bar Accuracy:±0,05 %FS Total Error Band:±0,1 %FS @-10…80 °C Line pressure:200 bar / 600 bar Interfaces:RS485, 4…20 mA, 0…10 V Special characteristics:Classic 'wet/wet'
Seria PD-39X - Nadajniki ciśnienia

Seria PD-39X - Nadajniki ciśnienia

The differential pressure transmitters of the PD-39X series measure the pressure difference indirectly using two absolute pressure sensors. The dual-sensor design with numerical differential formation also outputs the line pressure values via the digital RS485 interface and guarantees a high overload resistance. The additional analog current or voltage output is primarily used to output the differential pressure range, which is freely rangeable within the line pressure range. Pressure Ranges:0…3 to 0…300 bar Accuracy:±0,05 %FS Total Error Band:±0,1 %FS @-10…80 °C Line pressure:0…3 to 0…300 bar Interfaces:RS485, 4…20 mA, 0…10 V Special characteristics:Line pressure measurement
Seria 41X - Nadajniki ciśnienia

Seria 41X - Nadajniki ciśnienia

The capacitive pressure transmitters of the 41X series are designed for measuring relative pressure values in the mbar and µbar range. They use digital compensation with a mathematical model to achieve an accuracy of 0,1 %FS – in the temperature range from 10 to 40 °C, this value even corresponds to the total error band. In addition to the digital RS485 interface, the X-line transmitters have a rangeable analog current or voltage output. Pressure Ranges:0…1 to 0…200 bar Accuracy:±0,15 %FS Total Error Band:±0,7 %FS @ -10…80 °C Interfaces:I2C Temperature Range:-40…110 °C Dimensions:⌀ 19 mm x 5 mm
Seria 35X-Ei - Czujniki ciśnienia

Seria 35X-Ei - Czujniki ciśnienia

The front-flush pressure transmitters of the 35X-Ei series use digital compensation with a mathematical model to achieve exceptional accuracy of 0,05 %FS – in the temperature range from 10 to 40 °C, this value even corresponds to the total error band. In addition to the digital RS485 interface, the X-line transmitters have a rangeable, analog current or voltage output. Intrinsically safe – suitable for use in explosive atmospheres. Pressure Ranges:0…0,3 to 0…1000 bar Accuracy:±0,05 %FS Total Error Band:±0,1 %FS @ -10…80 °C Interfaces:RS485, 4…20 mA, 0…10 V Temperature Range:-40…120 °C
Seria 2Mi - Czujniki ciśnienia

Seria 2Mi - Czujniki ciśnienia

These low-cost miniature pressure transducers have been specially developed for very rapid hydrodynamic and aerodynamic in situ pressure measurements. The 2Mi sensors are available in a variety of housing designs and can simply be stuck on at the desired location. Despite its miniature design, the sensor chip is protected against external influences by a steel housing and a silicone elastomer coating. It can also be used in liquids. Pressure Ranges:0…1 to 0…400 bar Accuracy:±0,5 %FS Pressure Connection:Elastomer coating Dimensions:⌀ 4,5 mm x 3 mm Temperature Range:-20…80 °C
Seria 10LHP - Czujniki ciśnienia

Seria 10LHP - Czujniki ciśnienia

The high-pressure transducers of the 10LHP series have a robust housing made of stainless steel, giving them optimum long-term stability for a range of OEM applications. The metal diaphragm is welded on front-flush and gap-free, separating off the piezoresistive pressure sensor, which is made of silicon, from the measuring medium. Every pressure transducer is measured over the entire pressure and temperature profile and is supplied with a detailed calibration sheet. Pressure Ranges:0…200 to 0…1000 bar Long Term Stability:±0,25 %FS Dimensions:⌀ 19 mm x 15 mm Temperature Range:-20…100 °C Material:Steel 1.4435
LPX - AKCESORIA

LPX - AKCESORIA

The LPX low-pressure calibrator is a high-precision calibration instrument for pressures between -0,85 bar and 10 bar (after taring to ambient pressure). The functional calibrator is supplied in a sturdy carrying case and pressure can be quickly generated manually. It is therefore ideal for use in the field. The pressure is measured by the integrated LEX1 manometer and output both on the display and via the RS485 interface. Additional functions such as zero point resetting, peak and trough pressure value indication and leak measurement make it even easier to take measurements. Pressure Ranges:-0,85…10 bar Accuracy:0,05 %FS Interfaces:RS485 Display:5-digit LCD display Special characteristics:For air pressure
Seria TSC | Kondycjonator momentu i prędkości - Kondycjonator momentu i prędkości dla sygnałów czujnika momentu

Seria TSC | Kondycjonator momentu i prędkości - Kondycjonator momentu i prędkości dla sygnałów czujnika momentu

The TSC Series is the Torque and Speed Conditioner used to connect Magtrol Eddy-Current (WB) or Powder (PB) Dynamometers to the DSP7000 Dynamometer Controller. Powered by the dynamometer controller, and based on a precision instrumentation amplifier, the unit amplifies and filters the torque signal. It also provides power and connections for the speed pickup sensor which is located in the dynamometer. Offset:±0.2% (Full Scale Defection) Symmetry:±0.1% (Full Scale Defection) Bandwidth (3dB single pole):20Hz Offset Drift:<100ppm/ °C Sensitivity Drift:<50ppm/ °C Supply Voltage:±20 - ±30V Supply Current:40mA nominal / 45mA max. Torque O/P Voltage:5VDC ±0.2% Max. O/P Current:5mA Min. O/P Load:1kΩ
DCX-22AA-CTD - Rejestratory danych

DCX-22AA-CTD - Rejestratory danych

The DCX-22AA-CTD data loggers measure conductivity and temperature as well as pressure, along with the depth of bodies of water. They compensate for the air pressure using an additional, water-tight absolute pressure sensor with a stainless steel separating diaphragm. Unlike gauge pressure systems with a capillary tube, this system is completely resistant to moisture and can therefore be immersed. Thanks to their long-life battery, they can keep recording measurement results for years (up to 10 years at a rate of one measurement per hour). The logger can be configured using the supplied software (measurement interval, incident management, delayed measurement start etc.) and data that has been read can be displayed in a graph or chart, corrected using air pressure values, converted into fill levels or other units, and exported. Pressure Ranges:0…10 to 0…100 mH2O Total Error Band:± 0.1% FS @ -10 ... 40 ° C Reading capacity:114'000 measuring points Dimensions:ø 22 mm Special characteristics:Additional conductivity measurement
Seria TAB | Mocowania i Stoły - Systemy stołów i mocowania do ławek testowych

Seria TAB | Mocowania i Stoły - Systemy stołów i mocowania do ławek testowych

La table Magtrol pour freins dynamométriques et fixations permet de faire des tests en position fixe ou itinérante.
Seria PD-23 - Nadajniki ciśnienia

Seria PD-23 - Nadajniki ciśnienia

The differential pressure transmitters of the PD-23 series are designed for industrial applications and are supplied with a G1/4 internal thread as standard. They are based on a fully analog circuit. The PD-23 transmitters have a single silicon diaphragm in their interior, which is pressurised from both sides and measures the pressure difference directly. This design enables them to measure tiny pressure differences even at an extremely high line pressure. Pressure Ranges:0…0,2 to 0…20 bar Accuracy:±0,5 %FS Total Error Band:±4,0 %FS @ -10…80 °C Line pressure:200 bar Interfaces:4…20 mA, 0…10 V Special characteristics:Classic 'wet/wet' Temperature Range:-40…100 °C
Seria 4LD-Ei - Nadajniki ciśnienia

Seria 4LD-Ei - Nadajniki ciśnienia

The pressure transmitters of the 4LD-Ei series use the chip-in-oil technology developed by KELLER, uniting a pressure measuring cell, digital temperature compensation and signal processing in a compact housing made of stainless steel or Hastelloy. The transmitters are extremely resistant to environmental influences and delivery highly accurate measurement results as a digital output signal. The I2C interface and the low supply voltages make it easy to integrate in microcontroller-based systems. The extremely low power consumption is ideal for battery-operated devices. The D line is perfect for IoT solutions. Intrinsically safe – suitable for use in explosive atmospheres. Pressure Ranges:0…3 to 0…200 bar Accuracy:±0,15 %FS Total Error Band:±0,7 %FS @ 0…50 °C Interfaces:I2C Dimensions:⌀ 11 mm x 4,2 mm
HPX - AKCESORIA

HPX - AKCESORIA

The HPX high-pressure calibrator is a high-precision calibration instrument for pressures between 0 bar and 700 bar. The functional calibrator is supplied in a sturdy carrying case and pressure can be quickly generated manually. It is therefore ideal for use in the field. The pressure is measured by the integrated LEX1 manometer and is both shown on the display and output via the RS485 interface. Additional functions such as zero point resetting, peak and trough pressure value indication and leak measurement make it even easier to take measurements. Pressure Ranges:0…700 bar Accuracy:0,05 %FS Interfaces:RS485 Display:5-digit LCD display Special characteristics:For hydraulic oil
DSP 7000 | Programowalny Kontroler Wysokiej Prędkości - Programowalny kontroler wysokiej prędkości do hamulców momentowych

DSP 7000 | Programowalny Kontroler Wysokiej Prędkości - Programowalny kontroler wysokiej prędkości do hamulców momentowych

Le contrôleur haute vitesse programmable DSP7000 pour freins dynamométriques de Magtrol utilise les techniques les plus modernes de traitement de signaux et ouvre de nouveaux horizons aux essais de moteurs. Le contrôleur DSP7000, développé pour une utilisation avec les freins à hystérésis, les freins à courant de Foucault et à poudre, ainsi qu’avec des couplemètres de Magtrol et des systèmes auxiliaires, peut être commandé par PC moyennant une interface USB ou en option IEEE-488 ou RS 232. Avec sa vitesse de transmission de 500 points de mesure par seconde, le contrôleur DSP7000 se prête aussi bien à des utilisations très exigeantes en laboratoires de certification que sur des lignes de production. DSP7001 Mono-canal:solution avantageuse et d’utilisation aisée DSP7002 Bi-canal:permet de faire fonctionner simultanément deux équipements de manière indépendante Unités de couple au choix:anglaise, métrique et SI (standard)