The pressure transmitters of the 33X-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. 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.
Intrinsically safe – suitable for use in explosive atmospheres.
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.
The differential pressure transmitters of the PD-33X-Ei 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.
The capacitive pressure transmitters of the 41X-Ei 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.
The differential pressure transmitters of the PD-39X-Ei 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.
The pressure transmitters of the 7LC series use the chip-in-oil 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 deliver compensated measurement results as an analog, ratiometric 0,5...4,5V output signal over a wide temperature range.
The pressure transmitters of the 8LC series use the chip-in-oil 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 deliver compensated measurement results as an analog, ratiometric 0,5...4,5V output signal over a wide temperature range.
The pressure transmitters of the _LC series use the chip-in-oil 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 deliver compensated measurement results as an analog, ratiometric 0,5...4,5V output signal over a wide temperature range.
The 9FLC series is a special version of the 9LC pressure transmitter. The flanged housing can be mounted using an O-ring or welded on. As with all C-line products, the chip-in-oil technology developed by KELLER is used here, 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 deliver highly accurate measurement results as an analog, ratiometric 0,5...4,5V output signal over a temperature range of -40 °C to 150 °C.
The 9FLD series is a special version of the 9LD pressure transmitter. The flanged housing can be mounted using an O-ring or welded on. As with all D-line products, the chip-in-oil technology developed by KELLER is used here, uniting a pressure measuring cell, digital temperature compensation and signal processing in a compact housing made of stainless steel or Hastelloy.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.
The remote data transmission unit ARC1-Tube with logger function is encased in a robust, stainless steel housing, which is ideally suited to installation in 2" monitoring pipes. This unit records measurements made by external sensors (e.g. a level sensor) and periodically transmits the collected data via 2G, 3G, 4G, NB-IoT, LTE-M or LoRaWAN. The high-performance battery and sophisticated power management enable autonomous operation for up to 10 years. KELLER provides a range of licence-free software solutions for configuration and data processing. The easiest and most convenient way to access the collected data is via KOLIBRI Cloud.
The remote data transmission unit ARC1-Box with logger function is encased in a robust, water-tight aluminium housing. This unit records measurements made by external sensors (e.g. a level sensor) and periodically transmits the collected data via 2G, 3G, 4G or LoRaWAN. The high-performance battery and sophisticated power management enable autonomous operation for up to 10 years. KELLER provides a range of licence-free software solutions for configuration and data processing. The easiest and most convenient way to access the collected data is via KOLIBRI Cloud.
The remote data transmission unit ARC1-Box-SB with logger function is equipped with safety barriers and, in combination with intrinsically safe transmitters, it is suitable for use in hazardous applications. The unit is encased in a robust, water-tight aluminium housing. It records measurements made by external sensors (e.g. a level sensor) and periodically transmits the collected data via 2G, 3G, 4G or LoRaWAN. The high-performance battery and sophisticated power management enable autonomous operation for up to 10 years. KELLER provides a range of licence-free software solutions for configuration and data processing. The easiest and most convenient way to access the collected data is via KOLIBRI Cloud.
The remote data transmission unit ADT1-Tube is encased in a robust, stainless steel housing, which is ideally suited to installation in 2" monitoring pipes. The LoRa module, which can be configured on a country-specific basis, establishes a connection with the Internet and makes it possible to collect measurement data in a low-cost and energy-saving manner. These autonomous devices can be linked with digital level sensors and pressure transmitters in the KELLER D and X product lines. With three conventional, high-quality AA batteries, the system can operate autonomously for up to 5 years. The LoRaWAN provider can be selected freely or an in-house or open source infrastructure and associated services can be used. The easiest and most convenient way to access the collected data at the end of the transmission chain is via KOLIBRI Cloud from KELLER.
The remote data transmission unit ADT1-Box is encased in a robust, water-tight plastic housing. The LoRa module, which can be configured on a country-specific basis, establishes a connection with the Internet and makes it possible to collect measurement data in a low-cost and energy-saving manner. These autonomous devices can be linked with digital level sensors and pressure transmitters in the KELLER D and X product lines. With three conventional, high-quality AA batteries, the system can operate autonomously for up to 5 years. The LoRaWAN provider can be selected freely or an in-house or open source infrastructure and associated services can be used. The easiest and most convenient way to access the collected data at the end of the transmission chain is via KOLIBRI Cloud from KELLER.
KOLIBRI Desktop offers all the options for device configuration and displays current measured values and logger recordings in graph form. Thanks to the search and filter options, saved measurement data can be organised with ease and exported as an image, as an Excel or Word report, or in additional formats. All products in the KOLIBRI suite are inter-compatible and can exchange data with one another. The functions are continually being further expanded and optimised.
The Series PD-39 X does not measure the differential pressure directly – instead, it uses two absolute pressure sensors to take the measurement indirectly. As well as reducing costs, this differential pressure transmitter is also more robust in relation to unbalanced (one-sided) overloading. The differential pressure range should be at least 5% of the standard pressure range. Each pressure side has two pressure connections, so the Pressure measurements can be displayed and recorded on PC or Laptop with help of the software ControlCenterSeries30 (CCS30) and a seriel interface cable. Export of recordings to usual file formats possible. Up to 128 devices can be connected together into a KELLER Bus-system. The Series PD-39 X does not measure the differential pressure directly - instead, it uses two absolute pressure sensors to take the measurement indirectly. As well as reducing costs, this differential pressure transmitter is also more robust in relation to unbalanced (one-sided) overloading. The differential pressure range should be at least 5% of the standard pressure range. Each pressure side has two pressure connections, so the PD-39 X is easy to use in pressure lines So that the differential pressure can also be measured exactly if the standard pressure range/ differential pressure ratio is high, this series also features the tried-and-tested microprocessorbased technology that is used in Series 30 X. All reproducible pressure sensor errors (i.e. nonlinearities and temperature dependencies) are entirely eliminated thanks to mathematical error compensation. The sensor signals are measured with a 16-bit A/D converter, so the individual standard pressure ranges can be measured to an accuracy of 0,05%FS throughout the entire pressure and temperature range. Digital Interface The transmitters have a bus-compatible two-wire RS485 half-duplex interface which is modelled on the ”MODBUS RTU”. KELLER offers interface converters to RS232 or USB for use here. The READ30/PROG30 program and the protocol are freely available. The interface offers these capabilities: - Readout of pressure and temperature values for both sensors. This allows readout of the diffe- rential pressure as well as the two standard pressure ranges. - Calibration of zero points and amplification. - Scaling of the analog output to different pressure ranges or units. - Configuration settings such as measurement rate, low-pass (LP) filter, bus address, etc. - Readout of information such as serial number, compensated pressure and temperature ranges, etc. Analog Output The analog output is freely scalable via the interface. For flow measurements, the root of the differential pressure can also be outputted. The calculated value can be outputted via an analog interface (0…10 V or 4…20 mA).
The Series 41 X combines the ceramic measurement cell for low pressure ranges with the µP electronics of the digital Series 30 transmitter. The pressure values from the signals of the pressure and temperature sensors are determined by polynomial compensation (see reverse). The values can be displayed and stored on a PC via an RS485 interface and programming can also be carried out. The transmitters are calibrated to the base range. The PROG30 software permits programming of the analog output signal in each section of the range within the base range (e.g. range 100 mbar. Output 4…20 mA for 20…60 mbar). With KELLER RS converters K-100 Series, up to 128 transmitters can be hooked together into a bus system and read by means of a PC or laptop. READ30 software allows the current pressure of each transmitter to be read or the pressure activity of several transmitters to be recorded or stored whilst “on line”.
Piezoresistive pressure transmitter for applications in bio-reactors or autoclaves. The transmitter is compensated up to 150 °C and may be operated continuously or sterilised at this level, including the special circuit electronics The transmitters are supplied in absolute or gauge versions, with current or voltage output. The sensing component is a micro-machined silicon pressure chip of high sensitivity. An independent temperature sensor is integrated on the surface of the silicon chip
Series 22 DT was developed and homologated specially for use in so-called "bivalent" vehicles fitted with engines for combined natural gas/gasoline operation. The unconventional design with a small mass swept by the flow results in a fast response with temperature changes, the temperature being measured by an NTC or PT sensor located directly behind the stainless steel separating diaphragm. The same diaphragm transmits pressure via a capillary to a stress-free mounted silicon measuring cell. The signal processing for pressure and temperature is carried out by an electronic module connected to the sensors by flexible conductors. Mounted to the back of the electronic module, which is directly connected to the 6-pole plug connector are the EMC protection components. A special feature is the immunity from interference from electromagnetic fields up to 200 V/m.
Series 22 offers a reliable cost effective solution for customers requiring medium to high quantities, of mass produced transmitters. Utilising the KELLER automatic brazing lines, this new technology allows crevice-free construction of the pressure port with no internal seals or O-rings, making possible high volumes at low cost. In the brass 22 M, a steel insert and a nickel diaphragm are brazed into a brass housing. In the steel 22 S, all parts are stainless steel (AISI 316 L). The glass feed-through header and silicon pressure sensor are welded to the steel insert underneath the oil filling. The electronic circuit is fitted to the Packard plug. EMC-protection-components are mounted on the plug side, the amplifier on the sensor side. A flexible printed circuit “TAB” connects the sensor with the electronics. The transmitters are designed to have exceptionally good EMC ratings and operate over a wide temperature band, ideal for automotive, hydraulic and refrigeration control applications
LEO 2 is a compact, micro-processor (µP) controlled, highly accurate and versatile pressure measuring instrument with digital indication. The piezoresistive pressure transducer as the heart of the instrument has gone through extensive pressure- and temperature tests. Its characteristics are stored in the instruments internal EEPROM. The µP of the LEO 2 reads the characteristic values and calculates therefrom the pressure to an accuracy of < 0,1 %FS at room temperature. The pressure is measured twice per second and displayed. The top display indicates the actual pressure, the bottom display shows the Max.- or Min.- pressure since the last RESET. Also available as intrinsically safe version (LEO 2 Ei).
The LEO 5 combines the notable features of Keller’s successful LEO-Record and LEX 1 digital pressure gauges, featuring an IP66-rated stainless steel enclosure. This robust housing combines contemporary microcontroller-based electronics and capacitive-touch controls, operated through the environmentally-sealed safety glass front panel. The large backlit LCD display ensures readability in any lighting conditions. Two selectable measurement modes, standard and peak, are included to ensure maximum versatility. In standard mode, high-resolution pressure measurements are taken twice per second. When operating in peak mode, sampling frequency increases to 5 kHz with 16 bit resolution. The LEO 5 interfaces with a PC via USB connectivity, allowing access to active measurements and recorded data including pressure, peak pressure, temperature, and measurement interval. PC connection also allows device configuration, firmware updates, and recharging of the integral accumulator power supply. The unique modular design of the LEO 5 makes possible adaptation to customer-specific measuring requirements.
LEO 5 CA offers a user-friendly way to represent the pressure measurement at the bottom of a tank as the quantity of remaining liquid. At the push of a button, the microcontroller performs the calculations using the information of the tank shape and dimensions and displays the remaining tank content quantity on the clearly legible 5-digit LED display in the desired unit (litres, gallons etc.). The unit is configured using a PC and the easy-to-use software so that the filling level, which determines the pressure, can be converted into an appropriate filling quantity. First the tank shape is selected, then the tank dimensions and the specific gravity of the liquid are entered. It contains the most current tank shapes. The program covers the most common tank shapes, but also enables any shape by entering the parameters into a specified table. The exclusive use of absolute pressure sensors in the LEO 5 CA system eliminates the use of capillary vented cables with all the problems associated with a gauge pressure measurement. The LEO 5 CA housing integrates an air pressure sensor, ranged between 0,8 bar and 1,2 bar absolute. The sensors to measure the hydrostatic pressure at the bottom of the tank are calibrated from 0,8 to 1,8 bar abs for tanks up to 5 m in height, and 0,8 to 2,3 bar abs for tanks up to 10 m in height. The pressure difference, calculated by the micro-controller, is the relative hydrostatic pressure. The content of a pressurised tank is determined using the difference between the measurements from two absolute pressure sensors located at the top and bottom of the tank An accuracy of the system of up to 2 mbar (corresponding to a 2 cm water column) is achieved using a computerised calibration and compensation procedure for the pressure sensors. LEO 5 CA makes it possible to connect various pressure probe transmitter versions (with thread, front-flush with flange, or submersible sensors). The power supply to the system (8 to 28 V) can be provided externally or internally from an accumulator or a battery. The display is obtained by pressing the button on the front, and the value appears for a configurable duration. The LEO 5 CA has two switch outputs with configurable functionality and threshold values. The device must be supplied externally if the switch outputs are used.