Wednesday, May 31, 2017

Process Weighing Controller: The BLH G5 Tech Manual

G5 Instruments
BLH Nobel G5 Instrument (panel mount)

The G5 Instruments are high performance single-channel weight indicators (PM model, panel mounted) or weight transmitters (RM model, DIN rail mounted) intended for industrial systems.

The basic function is to convert the signals from strain gauge transducers to useful weight information. Transducer excitation is included as well as parameter controlled signal processing, indication of output levels, error supervision and operation of optional external equipment.

As long as the error supervision detects no error, a signal called ‘In process’ is then present but if an error is detected, ‘In process’ will be off and a specific error message will be displayed. ‘In process’ can be set to control any digital output. Note that there are weighing channel specific and instrument specific error detection.

All functions in the G5 Instrument are controlled by set-up parameters. Setting of parameter values can be done from the PM front panel. Set-up of a RM model must be done with a web browser in a PC that is connected to the instrument via Ethernet. Maintenance functions can be accessed locally (PM) or remotely (PM and RM).

View the complete Technical Manual below, or download the G5 Tech Manual from here.

Saturday, May 27, 2017

A Precise Combustion Airflow Measurement Station Designed for the Power Industry

The objectives in the power industry today are twofold;
  • To lower emissions 
  • Increase plant performance
Precise measurement of combustion airflow and fuel rates positively contributes to achieving those objectives, by providing the information needed to optimize stoichiometric ratios and facilitate more complete, stable combustion. Usable measurements cannot be obtained from existing devices such as Venturis, foils, jamb tubes, etc., or instrumentation such as thermal anemometers due to limited available straight duct runs, low flow rates, proximity to modulating control dampers, broad turndown range, and high concentrations of airborne particulate (flyash). 

There is a product, however, by Air Monitor Corporation that reliably and consistently provides precise combustion airflow measurement. The CA Station has both an integral airflow processing cell and Fechheimer-Pitot measurement technology and is engineered to meet the challenging operating conditions of the typical power plant. It's capable of providing mass flow measurement of PA, SA, and OFA within an accuracy of ±2-3% of actual airflow.
CA Station
The Air Monitor CA Station

While the main functions of primary air are to first dry and then pneumatically convey the pulverized coal from the mill to the individual burners, it also determines coal particle velocity at the burner exit, influencing the flame position relative to the burner tip and impacting flame stability, both key factors in achieving optimized burner performance. Accurate PA measurement obtained with a CA Station can contribute to reducing NOx and CO, improving flame stability, avoidance of coal pipe layout, minimizing LOI/UBC, reducing waterwall corrosion, and increasing combustion efficiency.

The CA Station is also ideally suited to measure SA entering each burner level of a partitioned windbox, SA being taken out of a windbox to supply multiple OFA ports, at the ducted inlet of FD fans, and bulk SA entering each windbox of a corner fired unit.

For more information about the CA Staton, contact Power Specialties by visiting http://www.powerspecialties.com or calling (816) 353-6550.

Tuesday, May 16, 2017

DAQ - Data Acquisition's Role in Process Control

Data acquisition
DAQ incorporating data acquisition, process
control, recording, display and networking
in a single compact unit
Courtesy Yokogawa Corp.
Data acquisition, like an equipment acquisition, is the procurement of an asset. Data is an asset. It helps an operator evaluate process or business conditions and make decisions that impact the success of the organization.

Let’s define data acquisition as the sampling of signals that represent a measurement of physical conditions and the conversion of those signals into a numeric form that can be processed by a computer. A data acquisition system will generally consist of sensors, transmitters, converters, processors, and other devices which perform specialized functions in gathering measurements and transforming them into a usable form.

Industrial process operators and stakeholders benefit from the collection and analysis of data by enhancing performance of valuable facets of the process or activity. Data acquisition, commonly known as DAQ, is widely employed in high stakes and sophisticated processes where there is a true need to know current conditions. A desire for increased profit drives the need for increased process output and efficiency. A desire to reduce risk of loss drives the need for reduced downtime and improved safety. Today, there are likely many useful applications for data acquisition that are not being tapped to their fullest potential. The modest cost and simplicity of putting a data acquisition system in place, compared to the benefits that can be derived from a useful analysis of the data for your operation or process, makes the installation of a data acquisition system a positive move for even small and unsophisticated operators in today’s market.

What we call DAQ today started in the 1960’s when computers became available to businesses of large scale and deep pockets. By the 1980’s, personal computers employed in the business environment could be outfitted with input cards that enabled the PC to read sensor data. Today, there is an immense array of measurement and data collection devices available, spanning the extremes of price points and technical capability. For a reasonable cost, you can measure and collect performance data on just about anything.

Data acquisition has an application anywhere an operator or stakeholder can benefit from knowing what is occurring within the bounds of their process or operation. Here is a partial list of the many physical conditions that can be measured in industrial settings:
  • Temperature
  • Pressure
  • Flow
  • Force
  • Switch Open or Closed
  • Rotational or Linear Position
  • Light Intensity
  • Voltage
  • Current
  • Images
  • Rotational Speed
Consider your industrial process or operation. Are there things you would like to know about it that you do not? Would you like to increase your insight into the workings of the process, how changes in one condition may impact another? Do you know what operating condition of each component of your process will produce the best outcomes? Is reducing maintenance, or heading off a failure condition before it occurs something you would like to have in your operation? Applying your creativity, ingenuity and technical knowledge, along with the help of a product expert, will help you get the information you need to improve the outcomes from your industrial process or operation. 

Monday, May 8, 2017

Wireless Instrumentation In Process Measurement and Control

Wireless Transmitters
Wireless Instrumentation (Yokogawa)
In process control, various devices produce signals which represent flow, temperature, pressure, and other measurable elements of the process. In delivering the process value from the measurement point to the point of decision, also known as the controller, systems have traditionally relied on wires. More recently, industrial wireless networks have evolved, though point-to-point wireless systems are still available and in use. A common operating protocol today is known as WirelessHARTTM, which features the same hallmarks of control and diagnostics featured in wired systems without any accompanying cables.

Wireless devices and wired devices can co-exist on the same network. The installation costs of wireless networks are decidedly lower than wired networks due to the reduction in labor and materials for the wireless arrangement. Wireless networks are also more efficient than their wired peers in regards to auxiliary measurements, involving measurement of substances at several points. Adding robustness to wireless, self-organizing networks is easy, because when new wireless components are introduced to a network, they can link to the existing network without needing to be reconfigured manually. Gateways can accommodate a large number of devices, allowing a very elastic range for expansion.

In a coal fired plant, plant operators walk a tightrope in monitoring multiple elements of the process. They calibrate limestone feed rates in conjunction with desulfurization systems, using target values determined experientially. A difficult process environment results from elevated slurry temperature, and the associated pH sensors can only last for a limited time under such conditions. Thanks to the expandability of wireless transmitters, the incremental cost is reduced thanks to the flexibility of installing new measurement loops. In regards to maintenance, the status of wireless devices is consistently transmitted alongside the process variable. Fewer manual checks are needed, and preventative measures may be reduced compared to wired networks.

Time Synchronized Mesh Protocol (TSMP) ensures correct timing for individual transmissions, which lets every transmitter's radio and processor "rest" between either sending or receiving a transmission. To compensate for the lack of a physical wire, in terms of security, wireless networks are equipped with a combination of authentication, encryption, verification, and key management. The amalgamation of these security practices delivers wireless network security equal to that of a wired system. The multilayered approach, anchored by gateway key-management, presents a defense sequence. Thanks to the advancements in modern field networking technology, interference due to noise from other networks has been minimized to the point of being a rare concern. Even with the rarity, fail-safes are included in WirelessHARTTM.

All security functions are handled by the network autonomously, meaning manual configuration is unnecessary. In addition to process control environments, power plants will typically use two simultaneous wireless networks. Transmitters allow both safety showers and eyewash stations to trigger an alarm at the point of control when activated. Thanks to reduced cost, and their ease of applicability in environments challenging to wired systems, along with their developed performance and security, wireless industrial connectivity will continue to expand.

For more information on wireless instrumentation, review the document below. Please feel free to call Power Specialties at (816) 353-6550 to speak with an applications specialist.