KOBOLD pressure sensors series PDD are cost-effective electronic pressure switches with digital indication of actual pressure. Two switch points, on / off-switch delay and hysteresis, are within the measuring range and are programmable.
A piezzo resistive ceramic sensor is used. The units can be used where high switching accuracy is needed. Long-term stability, repeatability and the compact and robust design makes them ideal for use in OEM applicaionts.
The Series 1000 and 2000 are a range of extra large 3 to 5 digit LED array displays, 125 mm digit height, designed to be used in process / temperature / weighing applications where high visibility and distant viewing is required. Using high intensity wide angle LED's in an IP65 enamelled steel housing ensures clear viewing distances of greater than 50 metres. For high ambient temperature conditions, an optional special coated glass window is available. Typical applications include downtime, time and production control in large factories, the indication of load cell inputs / crane overload protection, process signals such as temperature, pressure, level, and AC or DC voltages and currents. For electrical specifications, input signal details, as well as the terminal connector assignments in the Extra Large Display, see the individual indicator operating manuals (e.g. Model 4001). Standard DPM indicators are used and internally fitted for the internal signal conversion for the Extra Large Displays. (Models ending in a 2)
4 digit ASCII bus/DIG bus,45mm display
6 Digit ASCII bus/DIG Bus, 20mm display
8 Digit ASCII bus/DIG Bus, 20mm display
The high-pressure transducers of the 10LHP series have robust housing 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 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.
Technology
• Insulated piezoresistive pressure sensor encapsulated in an oil-filled metal housing • Ideal for mounting with O-ring and support ring • Typical output signal range of 160 mV/mA
Typical applications
• OEM • Industry • Laboratory • Oil and gas • Oceanology
The pressure transducers of the 10L series have a robust housing 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 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.
• Insulated piezoresistive pressure sensor encapsulated in an oil-filled metal housing • Ideal for mounting with O-ring • Typical range of output signal of 160 mV/mA
Typical Applications
• OEM • Industry • Laboratory
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.
The compact LEO2-Ei digital manometers are budget-friendly and provide high accuracy. The minimum or maximum value since the last reset can be displayed at the same time as the current pressure value in a wide variety of units of pressure. The swivel adapter allows the device to be optimally positioned. Power is supplied by a conventional CR2430 coin cell battery (provided).
Intrinsically safe – suitable for use in explosive atmospheres.
The high-accuracy LEO-Record-Ei digital manometers can record pressure and temperature autonomously for long periods thanks to their memory function. The data logger can be connected to a computer via the RS485 interface for configuration and for reading out the recorded data. The current pressure value can be displayed in a wide variety of units of pressure. Power is supplied by a high-quality 3,6 V lithium battery.
The pressure transducers of the PD-10L series have been developed to measure differential pressure. These OEM pressure transducers 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.
The low-cost OEM pressure transducers of the 6S series are based on a piezoresistive measuring cell with a brazed metal diaphragm in a steel housing.
The pressure transducers of the 9L series have a compact, robust housing made of stainless steel, giving them outstanding 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 .
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.
Ultramodern welding techniques and advances in the miniaturization of electronic circuits now make it possible to manufacture a pre-insulated, piezoresistive micro-transmitter with properties that were no more than a dream 10 years ago. The circuit is based on the PromComp principle which KELLER offered in a separate version as a laboratory device 20 years ago when it attained accuracy of 0,1 %FS over a temperature range of 100 K. In those days the electronic circuitry was the size of a cigar box, but now it can be accommodated on a print that is a mere 12 mm in diameter. Although this digital component is only slightly more expensive to produce than an analog circuit, it allows a piezoresistive sensor to be calibrated to an accuracy of 0,5 %FS over a potential temperature range of 100 K. A temperature sensor divides the temperature range into fields with a width of 1,5 K each. Two values are assigned to each field in an EEPROM: one value for the zero point and another for the amplification, determined by mathematical interpolation in the calibration process. During operation, the corresponding values are ‚switched in’ at the relevant temperatures. The electronics make it possible to assign up to 120 fields so that a temperature range of 180 K can be covered. The 100 K restriction for series 21 PY is due to the sensor This means that more or less any temperature can be the ‚calibration temperature’ for these transmitters. Calibration and temperature errors within a temperature field are within ± 0,2 %FS. The remainder of the error bandwidth of ± 0,5 %FS can be attributed to linearity and stability errors. So it’s goodbye to the days when sensor engineers had to struggle every day with TKN (zero point) and TKG (gain/amplification) problems. The 21 PY product line is outstanding due to its extreme ruggedness towards electromagnetic fields. The limits of the CE standard are undercut by a factor of up to 10 with conducted and radiated fields, thus making this product ideal for use in harsh industrial environments.
The Y-line transmitters have an extremely small temperature error. This is achieved using an additional circuit containing a temperature sensor that subdivides the temperature range into fields that are 1,5 Kelvin (K) wide. The TK zero and TK compensation values are calculated for each field and programmed into the additional circuit. During operation, these values are fed into the analogue signal path depending on the temperature. Each temperature is the "calibration temperature" for this transmitter. The Series 23 (S)Y/25 Y product line is outstanding due to its extreme ruggedness towards electromagnetic fields. The limits of the CE standard are undercut by a factor of up to 10 with conducted and radiated fields.
Digital Output of Transmitter: This high precision of 0,01 %FS is available as an option (the standard Series 33 X has an accuracy of 0,05 %FS). These Series are based on the stable, floating piezoresisitive transducer and the newly developed XEMICS micro-processor with integrated 16 bit A/D converter. Temperature dependencies and non-linearities of the sensor are mathematically compensated. Transmitter with Analog Output: Integrated in the XEMICS processor is a D/A converter of 16 bit for analog signal outputs of 4…20 mA or 0…10 V. The output rate is 400 Hz. The accuracy is diminished by this converting process by 0,05 %FS. The digital output is available on all transmitters with analog output. Programming With the KELLER software READ30 and PROG 30, a RS485 converter (i.e. K102 or K107 from KELLER) and a PC, the pressure can be displayed, the units changed, a new gain or zero set. The analog output can be set to any range within the compensated range. Accuracy and Precision “Accuracy” is an absolute term, “Precision” a relative term. Dead weight testers are primary standards for pressure, where the pressure is defined by the primary values of mass, length and time. Highest class primary standards in national laboratories indicate the uncertainty of their pressure references with 70 to 90 ppM or close to 0,01%. Commercial dead weight testers as used in our facilities to calibrate the transmitters indicate an uncertainty or accuracy of 0,025%. Below these levels, KELLER use the expression “Precision” as the ability of a pressure transmitter to be at each pressure point within 0.01 %FS relative to these commercial standards. The transmitter’s full-scale output can be set up to match any standard of your choice by correcting the gain with the PROG30 software.
The Series PRD-33 X was developed for applications that require a high accuracy differential pressure measurement together with high overload resistance in differential pressure ranges as low as 350 mbar. The Series PRD-33 X is the result of ongoing development of the KELLER PD-33 X differential pressure transmitter. Thanks to a second integrated pressure sensor, the line, or common mode, pressure can now be measured along with the differential pressure, resulting in several notable features not found in traditional differential pressure transmitters. For example, compensation for line pressure effect is now accomplished during factory calibration. Moreover, both differential and line (absolute) pressure may be read by the user. In addition, the PRD-33 X features high differential overload resistance; e.g., ± 35 bar with a differential measuring range of only 350 mbar (100:1). The internal differential pressure sensor element is isolated from the High (+) side media by a compliant stainless steel diaphragm, while the Low (-) side media impinges directly on the back side of the silicon measuring cell. Also isolated from the High (+) side media is the line (absolute) pressure sensor. The floating sensor assembly guarantees maximum decoupling from external mechanical forces. Another notable feature of the Series PRD-33 X is the robust digital RS485 bi-directional communication interface. Information such as serial number, pressure range, filter settings and process values for both differential and line (absolute) pressures and their temperatures are easily obtained. This combination of features enables certain measurements not possible with traditional differential pressure transmitters. For example, filling levels in liquefied gas storage tanks, including oxygen, nitrogen, carbon dioxide and argon can now be measured safely, accurately and at reasonable cost.
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.