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.
Proven primary pressure standard Deadweight Tester / Pressure Balances are the most accurate instrument available on the market for the calibration of electronic or mechanical pressure measuring instruments. The direct measurement of the pressure (p = F / A), as well as the use of high-quality materials enable a very small measurement uncertainty, in conjunction with an excellent long-term stability of 5 years (recommended in accordance with German Calibration Service DKD/DAkkS). The deadweight tester / pressure balance has therefore been used for years in factory and calibration laboratories in national institutes, research laboratories and in industry.
Stand-alone operation Due to its integrated pressure generation and the pure mechanical measuring principle, the model LR-Cal CPB5000-HP is ideal for on-site use for maintenance and service.
Basic principle Pressure is defined as the quotient of force and area. The core component of the model LR-Cal CPB5000-HP is therefore a very pecisely manufatured piston-cylinder-system, which is loaded with masses in order to generate the individual test points. The masses applied are proportional to the target pressure and this is achieved through optimally graduated weights. As standard, these masses are manufactured to the standard gravity (9.80665 m/s²), though the can be manufactured to a specific location (gravity) and also DAkkS-calibrated.
Easy operation The setting of the pressure is made via an integrated pump. For fine adjustment, a very precisely controllable spindle pump is fitted, with a spindle running within it. As soon as the measuring system reaches equilibrium, there is a balance of forces between the pressure and the mass load applied. The excellent quality of the system ensures that this pressure remains stable over several minutes, so that the pressure value for comparative measurements can be read without any problems, or also so that more complex adjustments can be carried out on the test item.
Robust instrument design With the high-pressure model LR-Cal CPB5000-HP, calibrations up to a maximum pressure of 5,000 bar are possible. It is built into a stable base and offers exceptional ease-of-use. With the integrated priming pump and the 250 ml tank, large test volumes can also be easily filled and primed.
Stand-alone operation Due to its integrated pressure generation and the pure mechanical measuring principle, the model LR-Cal CPB5600-DP is ideal for on-site use for maintenance and service.
Basic principle Pressure is defined as the quotient of force and area. The core component of the model LR-Cal CPB5600-DP is therefore a very pecisely manufatured piston-cylinder-system, which is loaded with masses in order to generate the individual test points. The masses applied are proportional to the target pressure and this is achieved through optimally graduated weights. As standard, these masses are manufactured to the standard gravity (9.80665 m/s²), though the can be manufactured to a specific location (gravity) and also DAkkS-calibrated.
Easy operation The pressure setting depends on the instrument design and is either done via an integrated pump or from external pressure supply via a metering valve. For fine adjustment, a very precisely controllable spindle pump is fitted, with a precisions spindle running within it. As soon as the measuring system reaches equilibrium, there is a balance of forces between the pressure and the mass load applied. The excellent quality of the system ensures that this pressure remains stable over several minutes, so that the pressure value for comparative measurements can be read without any problems, or also so that more complex adjustments can be carried out on the test item.
The LR-Cal CPB5600-DP instrument bases are available in the following four designs:
The instruments include the components of two pressure balances in one housing. For the calibration of differential pressure gauges under a static pressure, the two systems are separated by a by-pass valve.
One of the systems is used to generate the static pressure, with the second system generating the differential pressure (incl. static pressure). It is recommended that one of the sets of trim-masses is used for this (see accessories).
The instrument bases, pneumatic to 100 bar and hydraulic to 1,000 bar are fitted with quick-release meachnism. This enables a quick and safe replacement of the piston-cylinder systems without any tools. The pneumatic instrument design with separator is fitted with a connection for the piston-cylinder systems with M30 x 2 female thread and the hydraulic high-pressure base version is fitted with a M30x2 female thread with sealing cone.
The pressure test pump LR-Cal LPP 1000 is used to generate pressure for checking, adjusting and calibrating mechanical and electronic pressure measuring instruments by comparative measurements. These pressure tests may be carried out in laboratories, workshop or on site at the measuring point.
If the instrument to be tested and a sufficiently accurate reference measuring instrument are connected up to the test pump, the same pressure is applied to the two measuring instruments when the pressure test pump LR-Cal LPP 1000 is operated. By comparing the two measure valuses at random pressure values, the accuracy can be verified or the instrument under test can be adjusted.
Despite its compact dimensions, the pressure test pump LR-Cal LPP 1000 is easy to operate and allows for exact generation of the required test pressures The LR-Cal LPP 1000 is fitted with a fine adjustment valve for a precise adjustment of pressures.
The reference instrument is screwd directly on the top of the pump and the unit under test is connected by means of the connection tube incorporating an adapter 1/4" BSP female thread (freely rotating), contained in the scope of delivery.
Standard scope of delivery:
Proven primary pressure standard Deadweight Tester / Pressure Balances are the most accurate instrument available on the market for the calibration of electronic or mechanical pressure measuring instruments. The direct measurement of the pressure (p = F / A), as well as the use of high-quality materials enable a very small measurement uncertainty, in conjunction with an excellent long-term stability of 5 years (recommended in accordance with German Calibration Service DKD/DAkkS). The deadweight tester / pressure balance has therefore been used for years in factory and calibration laboratories in national institutes, research laboratories and in industry. Stand-alone operation Due to its integrated pressure generation and the pure mechanical measuring principle, the model LR-Cal LDW-H is ideal for on-site use for maintenance and service. Basic principle Pressure is defined as the quotient of force and area. The core component of the model LR-Cal LDW-H is therefore a very pecisely manufatured piston-cylinder-system, which is loaded with masses in order to generate the individual test points. The masses applied are proportional to the target pressure and this is achieved through optimally graduated weights. As standard, these masses are manufactured to the standard gravity (9.80665 m/s²), though the can be manufactured to a specific location (gravity) and also DAkkS-calibrated. Easy operation In the stable instrument base, the integrated priming pump and the 250 ml tank enable large test volumes to be easily filled and pressurised. For further pressure increases and find adjustment, a very precisely-controllable spindle pump is fitted, which only runs within the pump body. As soon as the measuring system reaches equilibrium, there is a balance of forces between the pressure and the mass load applied. The excellent quality of the system ensures that this pressure remains stable over several minutes, so that the pressure value for comparative measurements can be read without any problems, or also so that more complex adjustments can be carried out on the item under test
Proven primary pressure standard Deadweight Tester / Pressure Balances are the most accurate instrument available on the market for the calibration of electronic or mechanical pressure measuring instruments. The direct measurement of the pressure (p = F / A), as well as the use of high-quality materials, enable a very small measurement uncertainty, in conjunction with excellent long-term stability of 5 years (recommended in accordance with German Calibration Service DKD/DAkkS). The deadweight tester/pressure balance has therefore been used for years in factory and calibration laboratories in national institutes, research laboratories and in industry.
Stand-alone operation Due to its integrated pressure generation and the pure mechanical measuring principle, the model LR-Cal LDW-HK is ideal for on-site use for maintenance and service.
Basic principle Pressure is defined as the quotient of force and area. The core component of the model LR-Cal LDW-HK is therefore a very precisely manufactured piston-cylinder-system, which is loaded with masses in order to generate the individual test points. The masses applied are proportional to the target pressure and this is achieved through optimally graduated weights. As standard, these masses are manufactured to the standard gravity (9.80665 m/s²), though they can be manufactured to a specific location (gravity) and also UKAS (DAkkS)-calibrated.
Easy operation The integrated dual-area spindle pump enables rapid filling of the test system and smooth pressure generation up to 1,200 bar. At the same time, the precisely adjustable spindle pump also serves for fine pressure adjustment. A control schematic for pressure generation on the instrument base facilitates quick and easy operation.
As soon as the measuring system reaches equilibrium, there is a balance of forces between the pressure and the mass load applied. The excellent quality of the system ensures that this pressure remains stable over several minutes, so that the pressure value for comparative measurements can be read without any problems, or also so that more complex adjustments can be carried out on the item under test.
Compact instrument design The LR-Cal LDW-HK is also particularly notable for its compact dimensions, which are not altered during operation since the spindle runs within the pump body. With its compact dimensions, the exceptionally robust ABS plastic housing and the low weight associated with these, the LR-Cal LDW-HK is also particularly suited to on-site applications.
Digital manometers in the dV2 series from KELLER have versatile configuration options, with a max/min and zero function. The integrated microcontroller makes it possible to achieve [Genauigkeit|accuracies]] of up to 0,1 %FS. Larger unit quantities can also be programmed with tailored device functions in preparation for their subsequent use. The dV2 manometers are available with a range of housing designs and process connections, and can also be obtained as an OEM module.
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.