Accurate Thermal Metering Using Non-Invasive Technology For Building HVAC Energy Management

Non-invasive ultrasonic volumetric flow meter with temperature measurement for HVAC metering
Ultrasonic flowmeter specially configured for
thermal energy metering
Courtesy Flexim
The modern business climate has, for some now, been spooling up demand for accountability and, even more so, efficiency. Whether you think of efficiency as "doing more with less" or just avoiding the waste of financial, human, or natural resources the end result is the same and calls for similar prerequisites.

We live in a society of buildings, each with a mapped out function. Most buildings are predominantly occupied by people, bringing a requirement to maintain temperature, relative humidity, and air quality at levels of suitable comfort for human occupants. The energy consumption involved with providing that level of comfort stands as a bold line item in the operating expense ledger for any building. That is where accountability and efficiency come in. It is in the building stakeholders' interest to have knowledge regarding rates and quantity of thermal energy usage, as well as efficiency measures of delivered output per unit of input energy.

HVAC (Heating, Ventilation, Air Conditioning) primarily is an endeavor that generates and moves thermal energy throughout an enclosed space. Commercially available technology now allows a building operator to accurately measure that movement of thermal energy throughout a system or building. The process is generally called BTU metering and has a number of justifiable benefits.

  • Real time equipment performance measurement.
  • Sub metering can indicate specific areas of consumption.
  • Ability to directly bill multiple tenants in a single building for their thermal energy usage.
  • Monitor and balance energy flows.

BTU metering essentially involves inlet and outlet temperature measurement of heat transfer liquids, along with their flow rate. While the principle is simple, the intricacies of the measurement methods and equipment accuracy can have a substantial impact on the accuracy, and thus the benefit, of the measurement data. Additionally, adding more instrumentation to an already complex system can create an additional on-going maintenance and calibration burden to retain the necessary levels of accuracy and function. Success at gaining the benefit of the performance data while minimizing the additional maintenance burden due to the instrumentation should be the goal.

One solution calls for the use of clamp on ultrasonic flow meters to measure liquid flow, coupled with temperature measurement in a single unit that will perform necessary calculations and provide output data in useful engineering units. An overarching benefit of the clamp on meter is its non-invasive nature, allowing its retrofit to in-place systems with no disturbance to existing piping. Here are some other characteristics of a highly effective BTU measurement unit:
  • No wear mechanism as part of the flow measurement unit
  • Traceable accuracy of flow and temperature measurements
  • Simple installation in new or retrofit applications without disruption to system operation
  • Reliable and maintenance free operation
  • Accurate measurement from near zero flow rate to maximum system flow
  • Stable sensing with no zero drift
  • Communications protocol to match building energy management system
  • Large storage cache for data, in case of communication failure
  • Common output signals, 4-20 ma or other, usable with selected ancillary equipment
Selecting the right equipment or instrumentation is the most important step along the path of adding measurement capability to increase efficiency. Without a solid stream of reliable data, useful decisions become difficult. Contact a product application specialist and share your requirements and goals. Combining your process and system knowledge with their product application expertise will produce a good outcome.


Selecting Single-ended vs. Differential Voltage Measurement for Process Measurement - Part 2 of 2

programmable logic controller with input and output devices for process control
Selecting the proper signal conditioning equipment
is essential to maintaining process operation
This second part of a two part series of white papers provides discussion of the differences in function of differential and single-ended voltage measurement for industrial process measurement and control. Part One focused primarily on single-ended voltage measurement, how it differs from differential, and in what application context it can be best applied. This white paper, provided below, delves into differential voltage measurement and how it may be advantageous, even necessary, in a range of application scenarios.

The papers are produced by Acromag, Inc., a globally recognized manufacturer of signal conditioning equipment. Information about Acromag's extensive product offering is available from M.S. Jacobs & Associates, as well as technical details and application assistance.



Selecting Single-ended vs. Differential Voltage Measurement for Process Measurement - Part 1 of 2

DIN rail mounted process measurement signal conditioning module
Acromag manufactures an extensive array
of signal conditioning modules
Process control requires process measurement. The industry provides a enormous array of measuring devices for almost every conceivable process parameter. Selecting the right signal conditioner that will convert a current process state into a signal to be transmitted to and utilized by a controller can be challenging. One area of confusion centers around whether to use differential or single-ended voltage measurement.

Acromag, Inc., a globally recognized manufacturer of signal conditioning equipment for industrial process measurement and control, has provided a white paper that helps sort out reasons behind a beneficial selection of single-ended or differential voltage measurement devices. Explanation of how each functions and tips on selection criteria for an application are also provided. The technicality of the language is at a level that is comprehensible to most, but retains that exciting engineering edge for the purists among us. The first part of two (Part Two), provided below, focuses mostly on single-ended measurement. Part two covers differential.

Top flight assistance with your process measurement and control application challenges is available from M.S. Jacobs & Associates.



Get To Know MS Jacobs & Associates for Industrial Process Control Instruments and Equipment

Electric power generation plant
MS Jacobs serves the electric power generation industry,
as well as chemical, oil and gas, water and wastewater
M.S. Jacobs and Associates has been a leading manufacturer's representative and distributor of industrial instrumentation and controls since 1945.  Expanding from its original focus on the steel industry, MS Jacobs services and supplies products in all major industrial markets, including power generation, chemical processing, pulp and paper, oil and gas production, water and wastewater treatment, and nuclear power generation.

The company's longevity and dedication to the industrial market has resulted in a broad offering of superior quality products for flow, level, pressure, and temperature measurement, as well as filtration products and valves. Everyone at MS Jacobs takes pride in the company's ability to solve tough applications and provide exceptional customer service with a team of trained outside sales engineers and inside customer service representatives.

MS Jacobs' Pittsburgh service center provides instrument calibration and repair for MSJ's complete line of products, as well as those of other manufacturers. The company carries factory authorization for repair of numerous manufacturers' industrial process instrumentation products. The service center also provides custom assembly of instruments and other gear to meet customer requirements. Completed assemblies are tested and certified prior to shipment.

Reach out to MS Jacobs & Associates for the products and services that move your process instrumentation and control projects toward a successful completion.


Non-Invasive Measurement of Extremely Low Flow Rates




Industrial process measurement and control operations present a continuous stream of challenges to designers, engineers, operators, and equipment manufacturers. The innumerable combinations of environmental, safety, financial, and other concerns have lead to a wide variety of instruments, equipment, and techniques for meeting specific process requirements. A critical element of many industrial processes is the measurement of liquid flow. Matching the best available flow measurement technology or product to an application calls for through knowledge of the process, the medium being measured, and the strengths and limitations of a proposed measurement device. The most current product and application information is available from specialists in flow measurement.

The video illustrates how a special adaptation of ultrasonic flow measurement technology is utilized to measure extremely low flow rates. Specific product information is also included, showing the advantages and specific application ranges of this specialty product from Flexim Americas.


Oxygen or High Purity Service Valve Preparation

cutaway view of industrial ball valve for process control
Industrial Ball Valve
Courtesy Marwin Valve
Oxygen is used extensively throughout a wide range of industrial processes. Medical, deep-sea, metal cutting, welding, and metal hardening are a few examples. The steel industry uses oxygen to increase capacity and efficiency in furnaces. As a synthesis gas, oxygen is also used in the production of gasoline, methanol and ammonia.

Odorless and colorless, oxygen is concentrated in atmospheric air at approximately 21%. While O2, by itself, is non-flammable, it vigorously supports combustion of other materials. Allowing oils or greases to contact high concentrations of oxygen can result in ignition and possibly explosion. Oxygen service preparation of an industrial valve calls for special cleaning processes or steps that remove all traces of oils and other contaminants from the valve to prepare for safe use with oxygen (O2). Aside from the reactive concerns surrounding oxygen, O2 preparation is also used for applications where high purity must be maintained and valves must be free of contaminants.

Gaseous oxygen is noncorrosive and may be used with a variety of metals. Stainless steel, bronze and brass are common. Liquid oxygen presents unique challenges due to cryogenic temperatures. In this case, valve bodies, stems, seals and packing must be carefully chosen.

Various types of valves are available for oxygen service, along with a wide array of connections, including screwed, socket weld, ANSI Class 150 and ANSI Class 300, DIN PN16 and DIN PN40 flanged ends. Body materials include 316 stainless steel, monel, bronze and brass. Ball and stem material is often 316 stainless steel or brass. PTFE or glass filled PTFE are inert in oxygen, serving as a common seat and seal material employed for O2 service.

Common procedures for O2 service are to carefully deburr metal parts, then meticulously clean to remove all traces of oil, grease and hydrocarbons before assembly. Valve assembly is performed in a clean area using special gloves to assure no grease or dust contaminates the valve. Lubricants compatible with oxygen must be used. Seating and leakage pressure tests are conducted in the clean area, using grease free nitrogen. Specially cleaned tools are used throughout the process. Once assembled, the valves are tested and left in the open position. A silicone desiccant pack is usually inserted in the open valve port, then the valve ports are capped. A warning label about the desiccant pack's location is included, with a second tag indicating the valve has been specially prepared for oxygen service. Finally, valves are individually sealed in polyethylene bags for shipment and storage. Different manufacturers may follow slightly differing protocols, but the basics are the same. The valve must be delivered scrupulously contaminant free.

The O2 preparation of valves is one of many special production variants available to accommodate your special application requirements. Share your valve requirements and challenges with a valve specialist to get the best solution recommendations.

Video Reenactment and Analysis of Industrial Fire and Explosion

outdoor petroleum storage tanks at industrial facility
All facilities have some element of risk
Industrial accidents range in severity and impact from minuscule to catastrophic. As operators, owners, or technicians involved with industrial operations, we all have a degree of moral, ethical, and legal responsibility to conduct our work in a manner that does not unduly endanger personnel, property, or the environment. Maintaining a diligent safety stance can be helped by reviewing industrial accidents at other facilities. There is much to learn from these unfortunate events, even when they happen in an industry that may seem somewhat removed from your own.

The U.S. Chemical Safety Board, or CSB, is an independent federal agency that investigates industrial chemical accidents. Below, find one of their video reenactments of an explosion that occurred in Texas in 2013, along with their findings regarding the cause of the incident. Check out the video and sharpen your senses to evaluate potential trouble spots in your own operation.

Contact M.S. Jacobs & Associates for any safety related information you may need concerning their lines of industrial and process control products.