In the 23SX series high-precision pressure transmitters, temperature dependencies and non-linearity are precisely compensated for by means of a mathematical model in the microcontroller. In addition to the RS485 interface with Modbus RTU protocol, there is also the option of outputting the measurement results as a scalable analogue signal via the integrated D/A converter. The fully welded construction without internal seals is suitable for dynamic applications. Only stainless steel is in contact with the media.
The pressure transmitters of the 21C series with ratiometric 0,5...4,5V output combine chip-in-oil measuring cells with conventional electrical connections and pressure connections, making them ideal for industrial use. The transmitters are extremely resistant to environmental influences and deliver accurate measurement results over a temperature range of -40 °C to 125 °C.
The compact pressure transmitters of the 21Zio series can be used both as a pressure measuring instrument and as a pressure switch. Thanks to the universal IO-Link interface according to IEC 61131-9, the sensor is flexible and easily and quickly integrable into intelligent automation and other systems. The switching functions and other parameters can be called up and configured directly via IO-Link. In this way, machine downtimes are reduced to a minimum and personnel are relieved.
In the 23SXc series high-precision pressure transmitters, temperature dependencies and non-linearity are precisely compensated for by means of a mathematical model in the microcontroller. With the CANopen interface, KELLER offers a highly accurate pressure transmitter that is optimally suited for a wide variety of automation solutions. The fully welded construction without internal seals is suitable for dynamic applications. Only stainless steel is in contact with the media.
The pressure transmitters of the 9LD 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.
The highly dynamic and compact 21PHB pressure transmitter is suitable for use in liquids and gases, and can process pressure changes with a bandwidth of 20 kHz. This is achieved by means of the continuous analog signal that is adjusted by a digital circuit in real time and is amplified to a standardised 0...10V signal. The miniature sensor head with a fine M6 thread can withstand temperatures of up to 100 °C and is overload-proof up to a magnitude of four times the measuring range.
The pressure transmitters of the 22S series were designed for use in automotive and industrial applications. They are homologated and every one of their elements has been configured for optimum reliability. In this steel version of the 22 series, all parts that come into contact with media are made of stainless steel (AISI 316L).
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.
The pressure transmitters of the 23SY-Ei series are designed for elevated requirements in industrial applications. Thanks to its modular concept, this series is highly flexible and makes it possible to realise customer-specific requirements in very little time. The sophisticated compensation circuit makes it possible to specify a narrow total error band.
Intrinsically safe – suitable for use in explosive atmospheres.
The pressure transmitters of the 25Y-Ei series with a front-flush separating diaphragm are designed for elevated requirements in industrial applications and are supplied with a G1/2" male pressure port. Thanks to its modular concept, this series is highly flexible and makes it possible to realise customer-specific requirements in very little time. The sophisticated compensation circuit makes it possible to specify a narrow total error band.
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.
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 pressure transmitters of the 4LC 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 4LD 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.
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”.