Dodd-Frank Wall Street Reform and Consumer Protection Act Compliance

DFWSRCPA HeaderAs a responsible corporation and global citizen, Keller is pleased to participate in endeavors that aim to improve quality of life. Though, as a private corporation we are not required to do so,  we are pleased to comply with Section 1502 (DRC Conflict Minerals) of the Dodd-Frank Wall Street Reform and Consumer Protection Act.

To download a copy of our compliance statement, please click here.

New Keller Video Showcases Pressure Measurement Technology

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

New from Keller – PRD-33X differential pressure transmitter for closed tank level measurement


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 transmitters. 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.


– High-accuracy differential pressure measurement with compensated line pressure       dependency

– Differential pressure range from 350 mbar to 3 bar

– Pressure- and temperature-compensated

– Signal output: ΔP, base pressure, and temperature

– High overload resistance: ± 35 bar also in the 0…350 mbar measuring range

– Configurable via RS485 interface incl. software-manager for online data control, data save and programming

– Compact structural design including various electrical connections (binder, cable, M12)


– Level measurement of technical gases in liquefied gas tanks
– Differential pressure measurement in case of high unilateral overload resistance

Level measurement of pressurized tanks

Level measurement for non-pressurized tanks is a common application, and can easily be accomplished through the use of a “traditional,” relative-type level or pressure transmitter. The reason is that there is no pressure differential between the ullage pressure and barometric pressure. However, pressurized tanks present additional challenges.

In closed-system and pressurized tanks, two measurements must be made to calculate media level. Commonly, this is accomplished by using two separate pressure transmitters; one to measure tank pressure (liquid + ullage = P1), and one to measure ullage pressure (P2). Liquid level is then calculated by subtracting the ullage pressure value (P1-P2). Keller differential pressure transmitters make it possible to simplify the process with one instrument, as shown below:

Figure 1
Figure 1

In these more traditional applications, a standard differential pressure transmitter would prove adequate, however, other closed tank level applications, such as cryogenic storage tanks, require special transmitter capabilities.

Industrial Gas / Cold-converter systems / Cryogenics storage tanks

Cold storage and cryogenic tanks allow a large amount to be stored economically in a small space. However, the combination of low temperatures and precise level control requirements make standard differential pressure measurement increasingly difficult.

Figure 2
Figure 2

For example, during gas withdrawal the temperature and the pressure decrease. If the pressure drops below a defined threshold, liquefied gas is passed into a conduit outside of the insulation, where it is heated and vaporized, which will increase pressure. If too little or no gas is drawn, the inner pressure rises by taking in heat from the outside. If the upper threshold pressure is reached, gas is discharged into the environment which lowers the temperature and internal pressure. The logistics for these tanks is essential, and thus a continuous level monitoring is required.

Since the tanks are pressurized, the level measurement is more complex, as not only the liquefied gas column, but also the internal pressure needs to be measured to determine the liquid level. Additionally, varying tank size creates additional difficulties, as smaller tanks (< 3m) have particularly high requirements, since the pressure differential can be as low as 200 mbar (FS) with base pressure as high as 32 bar. When filling and manipulating the valves, the tank pressure may exert onesided on the differential pressure transmitter, while the air pressure is exerted on the other side. That‘s why a onesided overload of 32 bar is required.

Keller Differential Pressure Transmitter Comparison

Product Comparison

Differential pressure measurement provides a streamlined process for efficiently monitoring liquid levels in closed and pressurized tanks. As a world leader in level and pressure measurement instrumentation, Keller differential pressure transmitters are proven to provide outstanding accuracy and versatility to your changing needs.

Introducing the LEO 5

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

New Keller How-to Videos

Keller America is pleased to be able to offer the new How-to Video Series, featuring answers to commonly asked questions about Keller products and accessories. Click here to visit the new section, or select How-to from the support tab at the top of the page. Be sure to check back frequently for new content.

Also, if you have any suggestions for new videos, please let us know in the comments.

Keller Interface Converters

The K-114 interface converter replaces the existing K-104 converter, although this model will also remain compatible with all KELLER digital products in the future. This means that there is no need to replace existing converters.

The K-114 interface converter is used primarily in conjunction with KELLER products that have an RS485 interface, such as Series DCX, Leo Record, Series 3X / 4X or GSM-2.

The RS485 half-duplex signal from connected devices is converted into a USB signal by the interface converter, which can therefore be connected to any desired computer with a USB port.

For more information on Keller’s converters and their capabilities, click here.

Keller Digital Pressure Gauges

Keller digital pressure gauges (a.k.a. digital manometers) are a cost-effective solution in any pressure monitoring scenario where a local display is required. Features include min/max display, selectable units, 5 kHz scan rate for transient capture and data recording. These devices can also be built for service in oxygen applications.

These instruments are commonly used as fuel pressure gauges, hydraulic test pressure gauges, water pressure gauges and oil pressure gauges. Almost any installation previously utilizing mechanical or hydraulic pressure gauges can benefit from an upgrade to Keller technology.

Manufactured 100% in-house, Keller products incorporate the latest in microprocessor-based electronics and rugged, weather-proof enclosures, resulting in outstanding performance over a wide temperature range at reasonable cost.

For more information on the best Keller pressure gauge for your application, contact Keller today!

The move is on!

Keller America is pleased to announce that we will begin operations in our new state of the art facility on Monday, October 29, 2012.  The new facility incorporates the newest innovations in Keller manufacturing technology to allow us to provide the best possible quality and service to our customers.  To facilitate this transition, normal operations at our old location will be suspended on Thursday, October 24th and Friday, October 25th.  A customer service representative will still be available during normal business hours on these days to answer your calls.  Normal operations at the new facility will resume on Monday, October 29nd.

Please be advised that any orders taken for stock products and Keller America transmitters taken after October 19th may be affected during this transition.  Orders for stock products will be shipped as possible up until Wednesday, October 24th.  Shipments for stock products will resume on Monday, October 29nd.  Please allow 5-7 business days for shipment of Keller America level and pressure transmitters taken after October 19th.  After approximately one week in the new facility, normal three business day shipment of Keller America level and pressure transmitters should resume.

WaterWorld prodcast from ACE 2012 starring Chris Lilly

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!