Terminal Automation Solutions VITO Temperature Measurement
Temperature Measurement for Gauging Volume In order to determine the quantity of product present in bulk storage tanks, you need to take into account the product temperature in addition to the actual tank level as temperature is a determining factor for the volume and hence the density of a product. This factor is further intensified because temperature changes have an impact on tank characteristics, such as the tank roof, which moves as the temperature changes. These factors can be compensated for by means of accurate product temperature measurement. Besides product temperature the gas temperature should be taken into account, because liquid in the vapour phase also represents an economic value at the time of trading. Moreover, temperature information from the content of a tank assures better and safer process operation. Safe and Reliable Temperature Gauging The VITO (Versatile In Tank Observator) is an interface between the measurement probes and the level gauging offering. The intrinsically safe signals from the interface comply with all critical safety requirements applicable for hazardous environments. The VITO interface can be supplied with a wide variety of probes for temperature measurement, water bottom measurement or a combination of these. Honywell Enraf s product range also includes MRT and MTT probes in various types. Depending on type, besides product temperature they can also measure gas temperature and provide temperature profiling. VITO temperature gauging, depending on type, complies with the strictest requirements such as the API, ISO and OIML codes. The devices are internationally recognized by national weights and measures authorities and are therefore suitable for customs transfer applications. The VITO probe is a passive tool which enables intrinsically safe connection to the VITO interface. Both the probe and the interface are of explosion proof design in conformity to ATEX, and comply with the NFPA 70 requirements on electrical safety.
VITO An Accurate Basis Honeywell Enraf offers a comprehensive line of products for accurate temperature measurement. That line ranges from single spot temperature probes to the advanced VITO 16 element multiple thermosensor thermometer (MTT) for temperature and volume measurement technology. The gauging systems can easily be provided with additional functionality for water bottom measurement. With the VITO the number of instruments and components in and on the tank is kept to a minimum, while offering all benefits of accurate stock accounting. Proven benefits of Honeywell Enraf temperature gauging systems include: High measurement accuracy Minimal maintenance cost Flexible and simple installation Combine latest sensor technology with robust design Unique Measurement Principle The high degree of accuracy achieved by the VITO MTT and VITO LT range is attributable to a unique measurement principle. Whereas many other products measure absolute temperature, the measurements produced by these instruments are based on differential relative to a precise reference temperature detector (RTD). The measurement is performed by probes equipped with equidistantly spaced detector elements, 16 in the case of VITO MTT and nine in VITO LT. The accuracy achieved in this way is an impressive ± 0.1 C. The use of multiple elements compensates for any temperature differences between liquids. This function is particularly attractive in the case of bulk storage tanks, where the total content generally consists of batches that have not been loaded into the tank simultaneously. As a result, temperature differences may also arise between the various liquid layers. The VITO MTT and VITO LT allow for this factor. Even more, the use of multiple elements also enables temperature profiles to be determined. Notably in the case of liquid blends, that information offers considerable advantages. Measurement Systems for Any Application Honeywell Enraf temperature measurement instruments are available in different versions. Single spot temperature probes are available for simple temperature measurements. For more advanced measurements Honeywell Enraf supplies a complete range of VITO temperature measurement instruments, offering the appropriate solution for any operating environment and for fulfilling all customer requirements. Broad spectrum Your choice for a temperature gauging system will depend on the area of operation and/or the requirements as set forth by specification with regard to accuracy. For instance, in the case of intermediate storage and gas spheres, single spot temperature measurement may suffice, while for applications subject to weights and measures approval the VITO MTT or VITO LT is the instrument of choice. The following table outlines the applications, options and relevant solution. Application Measurement Temperature Measurement Measurement System Customs transfer, W&M approved Average product temperature VITO MTT Average gas temperature Temperature Profiles Customs transfer to API Average product temperature VITO LT Average gas temperature Customs transfer to API Average product temperature (MRT) VITO MRT Intermediate storage to API Average product temperature (PT100) VITO MRT Average gas temperature Intermediate storage Single spot temperature measurement Direct connection (PT100)
VITO Temperature Measurement Spot Temperature Measurement Honeywell Enraf supports and supplies spot temperature probes for direct connection to a level gauge. The probes can be attached at any desired location in the tank. Communication with servo or radar measurement systems can take place directly or via the VITO interface. Average Temperature Measurement VITO MRT For average temperature measurement based on resistance measurement the VITO MRT can be used in combination with multi-spot PT100 elements or with Multiple Resistance Temperature (MRT) elements. The combination with PT100 spot elements complies with API standards. For applications subject to weights and measures approval, the combination of VITO MRT with MRT elements is used. This solution provides an accuracy of up to ± 0.3 C, determined by the specifications of the MRT elements. Multiple Temperature Measurement VITO LT The VITO LT measures average product temperature and average gas temperature with an accuracy of ± 0.1 C. The temperature measurement is performed by a nine element probe developed by Honeywell Enraf. The VITO LT temperature measurement exceeds the requirements of all standards for in-tank measurements such as the API and ISO codes. Furthermore this version can be used with products stored at between -55 C and +135 C in tanks up to 20 meters high. Water bottom measurement can optionally be integrated in the VITO LT. Multiple Temperature Measurement VITO MTT The temperature measurement of VITO MTT is performed by a 16 element probe. The VITO MTT is able not only to measure average product and gas temperature but also to determine temperature profiles. It has a measurement accuracy of ± 0.1 C. Water bottom measurement can optionally be integrated in the VITO MTT. The temperature gauging system fully complies with all major standards for tank applications, such as API, ISO, OIML, NMI, PTB, etc. The VITO MTT is suitable for customs transfer purposes in conformity with national weights and measures regulations. In addition, the VITO MTT is fit for LNG storage. Product stratification and roll over caused by density variations due to temperature difference play an important role. In this environment the 16 element VITO MTT is an ideal solution.
Optimised and Convenient Solution Honeywell Enraf offers more than 45 years of experience, industry-leading products, optimised communication interfacing, fast installation and easy maintenance. The range of VITO temperature gauging systems easily interfaces with Honeywell Enraf s radar or servo storage tank gauging systems for a total solution for the determination of liquid level, water/product interface, volume and mass. All the data is available to higher level systems, such as DCS, SCADA or MIS systems. For this purpose the range is equipped with diverse communication protocols. VITO temperature gauging systems offer compact and lightweight design for simple installation in any environment. As VITO systems have no moving parts, limited maintenance is required.
Global Project Planning and Execution Capabilities Project requirements go further than specifying a number of products and systems. Honeywell Enraf s staff is dedicated to your project throughout all stages: involve all relevant departments in the early project stages go through a survey guidance through the design process for optimum solutions to reduce costs provide support with a team of experts via our global excellence centres Design Site survey Feasibility study Scope definition Functional design Products selection Implementation Parts procurement System engineering Application development Supervision on installation System integration Operation Commissioning Acceptance testing Training System optimisation Service and support For More Information To learn more about Honeywell Enraf s solutions, contact your Honeywell Enraf account manager or visit www.honeywellenraf.com. Americas Honeywell Enraf Americas, Inc. 2000 Northfield Ct. Roswell, GA 30076 USA Phone: +1 770 475 1900 Email: enraf-us@honeywell.com Asia Pacific Honeywell Pte Ltd. 17 Changi Business Park Central 1 Singapore 486073 Phone: +65 6355 2828 Email: enraf-sg@honeywell.com Europe, Middle East and Africa Honeywell Enraf Delftechpark 39 2628 XJ Delft The Netherlands Phone: +31 (0)15 2701 100 Email: enraf-nl@honeywell.com EN-10-04-ENG May 2010 2010 Honeywell International Inc.