Posts Tagged ‘keller’

RFID Technology Streamlines Process for Mandatory Hydraulic Inspection

Tuesday, April 12th, 2016

Giant machines require hydraulic testing

The mining and construction industries use huge machines to drill, dig, haul, plow, and carry earth. Each of these machines contains several hydraulics systems to perform their duties; all of which require periodic testing to verify function and safety.


The current testing method involves the use of expensive external measurement devices that must be connected to each test point sequentially each time a test is required and is therefore very time consuming. The highly manual process also can be very unsafe and unreliable which can lead to longer down times or, worse yet, employee injury.
Keller RFID pressure transmitter

Keller RFID pressure transmitters provide a faster, safer, and less-costly option than the current industry test method. RFID transmitters simplify the process and significantly reduces machine down time, while increasing reliability, accuracy, and worker safety.


To best understand the benefit of the Keller RFID solution, we must first consider the current generally accepted testing procedures, and the problems associated with each step. Each system must be tested, one point at a time, until all functions are verified. Depending on the equipment, there could more than a dozen separate hydraulic systems, involving the brakes, steering, transmission, and hopper lift.


For each system, the applicable hydraulic cylinder must be accessed, a service port opened, and a pressure measurement device connected. As soon as the service port is opened, however, there is great potential for fluid loss or contamination, or the ingress of air into the hydraulic system…each condition resulting in potentially dangerous situation and costly repair.


Typical analog gauges for hydraulic testingIn most cases, inspectors will attach an analog pressure gauge to a hydraulic hose which is then connected to the cylinder to be tested. An operator will then cycle the system and manual measurements will be taken at predetermined test points. While the accuracy of these reading relies heavily on a properly bled system, the greatest source of potential error results from the manual process of reading and recording the values.


Once the procedure is complete, workers must reverse the process to return the hydraulics system to working order. Again, each step repeats the possibility for problems and system damage. Then, after all of that, they can move on to the next of several hydraulic systems.


Now imagine, if you will, that each step occurred without difficulty. Great, right? But just think of the amount of time that it would take to complete one system check, multiplied by all the on-board hydraulic systems. The total down time represents a huge loss of productivity, and considering the cost of just one of these machines, minimizing down time presents a great opportunity for cost savings.


Keller RFID loggersInstead, let’s consider the Keller RFID solution. By permanently installing a Keller RFID transmitter in place of the service port on each hydraulic system, the tester need only cycle the system and take the necessary measurements with the wireless RFID scanner. No fluid loss or contamination, no air bleeding, and no misreading. The total test time drops from hour(s) per system to minutes with a marked increase in worker and system safety.


RFID reader for Keller Series 21D RFIDClick here to learn more about the RFID solutions from Keller. If you have any questions, or would like to discuss your application in greater detail, please feel free to contact Keller using the online contact form, live chat, or call 877-2-Keller.

Online quote forms now available!

Wednesday, March 16th, 2016

At Keller America, we have always worked to improve the experience for our customers. And, to that end, we are rolling out several new quote request forms for many of our most popular products, starting with all U.S.-made products.

Keller America Quote Form

Keller America now offers online quote forms for several products.


The quote forms can be accessed through the product specific pages for the Acculevel, Acculevel SDI, Digilevel, Econolevel, Levelgage, LevelRat, Microlevel, and Nanolevel submersible level transmitters and Econoline, Preciseline, Preciseline SDI, and Valueline pressure transmitters with forms for more products to be  added over the coming weeks. These forms include fields for all specifications necessary for our associates to generate a complete quote. However, if your application has unique requirements, or you are unsure about the best product for your needs, please feel free to take advantage of our web contact form, live chat, or toll-free phone number.


Keller LevelRat keeps getting better!

Wednesday, October 14th, 2015

2015 has been a big year for the LevelRat. First, it gets an accuracy upgrade effectively doubling its Total Error Band accuracy. Now, the LevelRat comes equipped with dual outputs; one analog and one digital.

The analog outputs you know: 4-20 mA, 0-5 VDC, or 0-10 VDC. These outputs are industry standards and ensure compatibility with most existing infrastructure. But, this is the digital age so digital we shall be. Keller has added RS485 digital communications to the LevelRat opening a whole new world of options and compatibility to arguably the best alternative for wastewater level measurement.

The RS485 output the same Modified-MODBUS communication protocol as Keller’s other digital transmitters. This feature makes direct connection to MODBUS SCADA, PLC, and RTU units possible, allows up to 128 transmitters to be connected on a single bus, and facilitates connection to a PC running Keller’s intuitive CCS30 software which gives users the ability to actively view real-time pressure/temperature changes, run software-assisted level logging, and make adjustments to the analog output to meet your changing requirements.

And yet with all these upgrades, the LevelRat is still built to order in the U.S. in 3 short business days, or less. And the 4-20 mA versions still include Keller’s guaranteed lightning protection. Click here for more information on the LevelRat non-fouling level transmitter.

It is our goal to provide the very best products for your level and pressure measurement needs. We look forward to the opportunity to prove it.


LevelRat Non-fouling Level Transmitter Receives Accuracy Upgrade

Monday, May 18th, 2015

Keller LevelRat
Since the Keller LevelRat was introduced, it has challenged the conventional wisdom of wastewater level measurement. The LevelRat has proven that wastewater level transmitters need not be bulky and expensive, that non-stick diaphragms don’t need to be large and fragile, that custom configurations can be achieved without long lead times, and that guaranteed lightning protection is a right, not a privilege.

And, though it may seem impossible to improve on a product of such significance, Keller has done it.  The LevelRat now provides even better accuracy (0.2% FS Static and 0.5% FS Total Error Band), representing double the accuracy under real-world conditions while maintaining the same low price. Isn’t that what you should expect from your level and pressure transmitters? Real value? We think so, too.

For more information on the LevelRat non-fouling submersible level transmitter, click here.

OEM Transmitters : All-inclusive

Tuesday, July 8th, 2014

By Daniel Hofer, Dipl.EL.-Ing FH and Bernhard Vetterli, Dipl, Dipl.El.-Ing.HTL

Miniaturization in pressure measurement technology

Keller’s OEM transmitters are systems that can be described as “embedded” in the best sense of the word – and in two different ways. First the sensor and the downstream electronics are embedded in the same housing. And second, the transmitter capsules themselves are ideally suited for embedding in application-specific systems. Depending on requirements, the output signal is standardized and temperature-compensated (ratiometric or digital).

Thanks to Chip-in-Oil (CiO) technology developed at Keller, the trend toward sensor miniaturization is now a reality. This development can offer impressive advantages: an extremely compact structural design, high resistance to electrical noise fields, and high vibration resistance thanks to low mass and short conduction paths.

To put it clearly, CiO technology means that an ASIC is fitted directly next to the pressure sensor – in the same housing – to provide users with a whole range of beneficial functions. However, this does not make the pressure measurement capsule any larger;  Its external dimensions remain the same. This transmitter concept is available in housings 4L…9L, starting from a diameter of 11mm.

Sintered-in pressure-resistant glass lead-throughs feed the transmitter signals outward. The internal Wiring uses short, lightweight bonding wires – with the total exclusion of air in oil. First, this approach eliminates the need to connect filigree signal processing boards with multi-wire cabling in the rest of the installation process for the pressure transducer. And second, there is no need to protect the downstream electronics against moisture and condensation.

Together with the high-grade steel housing, the glass lead –throughs act as feed through capacitors, forming a Faraday cage. This makes the CiO technology extremely resilient to electrical fields. Even field strengths of 250V/m at frequencies of up to 4GHz are unable to influence the measurement signal. The digital interface must be protected by the equipment manufacturer itself.

The ASIC is designed as a microcontroller with the corresponding peripherals, so the sensor signals can be registered with high resolution and dynamism. In addition to the process pressure as such, the temperature of the pressure sensor is measured and is used for mathematical compensation when the signal is processed.

OEM transmitters supply two signals: a ratiometric analog voltage output and a digital inter-integrated circuit interface (12C).

Ratiometric output signal

The secret of the ratiometric format to the output signal is that it actually has no format at all, because it depends on the voltage supplied. This is an inestimable advantage for applications in integrated systems. If the analog-to-digital converter downstream of the transmitter is operated with the same supply voltage, the digital measured value will always be correct. This is because the height if the digitization steps depend on the voltage supply, but the number of steps does not – and their number is the critical factor. Using ratiometric signals substantially reduces the outlay on passing signals from the pressure transmitter to the A/D converter in the downstream electronics, and calibration steps are unnecessary; in the specific case of connection to a microcontroller with an integrated A/D converter, this outlay equals zero. Nevertheless, an interval is specified for the output signal, i.e. 0.5…4.5V for s supply voltage of 5.0V. With a stable and precise supply voltage, this interval can also be used directly as the “standard signal.” The sampling rate of 2 kHz offers amazingly good dynamic scope for a product based on the AD/DA principal. Moreover, the embedded electronics in CiO technology provide constant protection against overvoltage and polarity reversal on all lines up to ±33 VDC.

Embedded interface I2C

OEM transmitters that are the same size as pressure measurement capsules are never connected directly to field bus systems. Instead, the respective coupling modules have corresponding input interfaces, e.g. for the inter-integrated circuit or I2C interface. For years, this has been the serial standard to cope with short distances in embedded systems. The I2C master needs two lines for the serial data and the pulse (clock) for synchronous sampling. Consequently, no timing requirements are specified for the master – which, in fact, determines the timing. Each OEM transmitter has its own address, which is addressed by the I2C master. In the existing configuration, one master could manage 128 different addresses. The pressure and temperature values are registered by means of a request from the master, and are then available at the transmitters (slaves) after less than 10ms, so that they can be clocked out according to a specified protocol. The values are temperature compensated and standardized, and they only need to be scaled from the 15-bit integer to a pressure and/or temperature with units.

Mobile Application

Unlike the CiO version with the ratiometric output, CiO versions with I2C output can operate with a voltage supply of only 1.8…3.6 VDC, so they are excellently prepared for mobile battery-powered applications. In this case, however, features also include the short conversion time of less than 10ms (during which a mere 1.5mA is drawn) and the excellently optimized Sleep mode: unless they are polled, the transmitters remain in this mode, which is typically specified as 0.1µA. If the master allows suitable fast communication, 100 samples per second can be therefore be attained.

OEM transmitters for Everyone

Typical key data vary according to the format of the output signal – ratiometric or digital. With an analog output, the transmitter can be used at temperatures between -40°C and +150°C, whereas the I2C output is subject to an upper limit of 80°C. The pressure range for the analog version extends from 2 bar to 1000 bar; for the digital version, the range is from 2bar to 200 bar. For a greater dynamic scope with increased power consumption up to a maximum of 8mA, the analog version should be chosen. For low voltage and low power applications, the digital version (which also provides temperature information) is recommended.


Keller’s C-series OEM transmitters herald a new chapter in the history of high-integration pressure measurement technology. The Chip-in-Oil concept moves signal processing directly into the protective oil-filled pressure measurement capsule housing, made of stainless steel. Linearization, temperature compensation and parameterization are handles here. For integration into higher-level systems or battery-powered devices, versions are available with ratiometric voltage output or with a serial-digital I2C interface. Various structural designs can be supplied depending on the specific application.

New Keller Video Showcases Pressure Measurement Technology

Thursday, April 3rd, 2014

This newly produced video details Keller’s origins and the products that have made it a world leader in pressure measurement technology.

Introducing the LEO 5

Wednesday, June 26th, 2013

Keller is pleased to announce the new LEO 5 digital pressure gauge. It is the first Keller gauge to incorporate a stainless steel housing, safety glass face, rechargeable accumulator power supply, and capacitive-touch controls. Plus, the back lit LCD display ensures readability in any lighting condition.

This new instrument combines Keller’s proven piezoresistive measurement capability with enhanced microprocessor circuitry to deliver outstanding accuracy, and maximum capability.  The unique combination provides 2 measurement modes: Standard for high resolution pressure measurement and Peak for 16 bit resolution at a rate of 5kHz.

The LEO 5 also provides an integral data logger; storing pressure, temperature, and time/date. This interfaces with a PC for data retrieval, device configuration, firmware updates, and accumulator recharge.

Several options are available to ensure compatibility with a variety of applications in new or existing systems. For more information call 877-253-5537, emails, or visit

WaterWorld prodcast from ACE 2012 starring Chris Lilly

Tuesday, July 24th, 2012

Chris Lilly discusses Keller level and pressure transmitters with Angela Godwin with WaterWorld. We have had a great deal of success with the AWWA tradeshow and we look forward to next year’s show. Special thanks to WaterWorld and Angela Godwin for the footage!

Construction is underway!

Monday, January 16th, 2012

Keller America is pleased to announce that construction has begun on their new facility. Scheduled for completion in early to mid autumn, this building will house the newest innovations in Keller manufacturing technology to better serve our continually growing customer base. We would like to thank each of you for your support of Keller products, and look forward to the new opportunities that this facility will provide.

Along with the increased production capabilities, Keller is also proud that this facility is on the leading edge of environmentally friendly construction, utilizing geothermal climate controls and construction materials chosen to provide outstanding durability and minimize environmental impact.

In addition, all irrigation will be provided by captured rainwater. Since Keller instruments are often used for applications like this, Keller will install several of their own DCX, GSM, and liquid level instruments for level monitoring and control. These systems will also serve as a training opportunities for customers and employees, alike.

New Keller Manufacturing Process Video!

Wednesday, June 29th, 2011

New Keller Manufacturing Process Video!