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The latest expansions and contractions - September 2016

Thu, 29 Sep 2016 11:24:00 -0400

Rockwell Automation acquires Automation Control Products; Schneider Electric, Honeywell unveil new product offerings.

PID Options and Solutions - Part 1

Wed, 28 Sep 2016 19:04:00 -0400

The major types of process responses and the different worlds of process applications are presented. Additionally, the oversight of not including and understanding the contribution of automation dynamics is addressed. The discussion of the response of the PID is started. The following key points support and augment the PID Options and Solutions - Part 1 recording for the ISA Mentor Program. 1-1: The most common type of process by virtue of the very common flow loop has a self-regulating response where the process will reach a steady state with the PID in manual for a given disturbance or change in PID output due to negative feedback within the process. 1-2: The response of the more important continuous processes for temperature, composition and pH control more directly related to product quality and process efficiency and capacity usually have an open loop time constant that is more than 4 times the total loop deadtime. In these cases, the PID controller, in its typical response time frame of 4 dead times, sees a ramping process. So far as the PID is concerned, the process appears to be integrating. It is extremely used to treat these processes as near-integrating and analyze them and tune them as integrating processes. You can easily convert between the integrating process open loop gain and the self-regulating process open loop gain and time constant. 1-3: Batch processes for temperature, composition and pH control typically have a true integrating response (no steady state) that is caused by zero negative feedback within the process in the normal operating range.  Level and gas pressure systems have a true integrating response. 1-4: The temperature control of highly exothermic chemical reactors, the cell concentration of bioreactors in the exponential growth phase, and the speed control of some axial compressors in surge have a runaway response characterized by acceleration due to positive feedback within the process. 1-5: Processes with slow or no negative feedback or that have positive feedback rely much more on the PID controller to provide the missing negative feedback that is best done by PID gain action. PID integral action is not as effective and can be detrimental if it is greater than the PID proportional action. This will be seen in in subsequent recordings as the slow large oscillations caused by a PID gain too small relative to the reset time.  Process control is achieved by negative feedback. The less negative feedback in the process, the more you need to rely upon the negative feedback provided by the proportional mode. 1-6: To compensate for a disturbance or to achieve a new setpoint for near and true integrating and runaway processes, the PID output must be driven past its Final Resting Value (FRV). 1-7: The most common metric for loop performance cited in the literature is an integrated absolute error (IAE).  This IAE is the area between setpoint (SP) and process variable (PV) on a trend recording. It can be representative of the total amount of material that is off-spec. 1-8: Of more immediate value is the peak error that is the maximum excursion of the PV from the SP. A large peak error can trigger side reactions, Safety Instrumented System (SIS) activation, cell death, and relief devices to blow. 1-9: PID PV overshoot for a setpoint change can have many of the undesirable effects of a peak error. 1-10:  PID output overshoot of the FRV is problematic for many self-regulating hydrocarbon processes with extensive heat integration and recycle. 1-11: Minimizing time to reach setpoint (rise time) is important to minimize the startup and transition time of continuous processes and the cycle time of many batch processes. There is typically a tradeoff between minimizing rise time and PV overshoot. For bioreactors, the cells are so sensitive and the batch cycle times are so slow that minimizing the overshoot for temperature and pH shifts is much more important, particularly for mammalian cell cultures. 1-12: Pulp, paper, food and polymer inline, extrusion and sheet processes m[...]

2016 State of Technology Report: The latest trends in power systems

Tue, 27 Sep 2016 15:55:00 -0400

Control’s latest State of Technology report delves into the many aspects of power systems of interest in process plants.

Ask The Experts: Control valve for cavitating acids?

Tue, 27 Sep 2016 10:47:00 -0400

Experts weigh in on which control valve can be used that will withstand cavitating acids.

Wago's Epsitron Eco slim power supplies

Mon, 26 Sep 2016 12:56:09 -0400

New offerings are EN 60335-1 standard-compliant, highly versatile, and have DIN-35 rail- and chassis-mount options, and a small profile.

Commercial off-the-shelf technology to the rescue, again

Mon, 26 Sep 2016 12:13:00 -0400

‘It lets us take and move more data, do more computing, archive more process lore, make comprehensive and complex analyses, and make better decisions,’ says Paul Studebaker.

Bimba’s IntelliSense smart technology platform

Fri, 23 Sep 2016 13:48:03 -0400

Helps to create intelligent production systems that communicate real-time information to evaluate the potential life cycle of pneumatic components.

Enbridge Inc., Spectra Energy Corp. to merge

Thu, 22 Sep 2016 14:26:00 -0400

Will create the largest energy infrastructure company in North America with an approximate value of $127 billion.

Plantman Go: The future of asset lifecycle modeling

Thu, 22 Sep 2016 11:33:00 -0400

Capture asset information in a unified, integrated lifecycle model—from design to decommissioning.

‘Gain Access’ with FieldComm Group

Thu, 22 Sep 2016 10:13:00 -0400

HART, FOUNDATION Fieldbus and FDI connect the Industrial Internet of Things. Learn more in this report from FieldComm Group.

AutomationDirect’s Rhino Series power supply

Wed, 21 Sep 2016 13:15:03 -0400

Offers high performance and reliability without features of high-cost supplies.

DCS market to decline and recover: ARC Advisory Group

Wed, 21 Sep 2016 12:04:00 -0400

Latest research study projects slowing decreases and gradual gains for distributed controls.

Demonstration of a destructive cyber attack vector on “air-gapped” systems

Wed, 21 Sep 2016 10:45:00 -0400

All too often, people claim their systems are air-gapped, and therefore have no cyber vulnerability. But Alternating Current (AC) power cords cross the ostensible “air gap”, and power supplies for laptops, servers, ICSs, etc. have rarely been addressed for cyber security vulnerabilities. This demonstration will remotely cyber attack and permanently disable a fully air-gapped system – in this case, a server, a router, and a PLC connected only to each other.

Quint power supplies

Tue, 20 Sep 2016 16:11:07 -0400

Provide improved configuration and diagnostics to ensure reliable power to the control system.

ExxonMobil’s patented progress toward integrating control systems, IT

Tue, 20 Sep 2016 12:27:00 -0400

Ian Verhappen explores how the company is pushing IIoT ‘near the edge’

MCAA expects slowing process instrumentation, automation growth

Tue, 20 Sep 2016 10:00:00 -0400

PIA markets in the U.S. and Canada expected to slow over the next five years to 3.1% during 2015-2020.

Dr. James Truchard to retire as National Instruments CEO, president

Mon, 19 Sep 2016 15:31:00 -0400

Company's board of directors has elected Alex Davern to succeed him, effective Jan. 1, 2017.

How Protocol Conversion Addresses IIoT Challenges

Mon, 19 Sep 2016 10:59:00 -0400

This white paper from Red Lion explains protocol conversion and details how organizations can connect devices, monitor processes, and control operations to extend equipment lifespan.

Beckhoff Automation’s EtherCAT P

Mon, 19 Sep 2016 10:46:35 -0400

Integrates the EtherCAT Ethernet communications protocol and peripheral voltage into one four-wire Ethernet cable.

AutomationDirect’s ZIPport products

Mon, 19 Sep 2016 10:23:34 -0400

Includes Mini Size 1 cables, cordsets, connectors, T-couplers and receptacles.