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Schneider Electric details DCS at Foxboro event

Wed, 20 Sep 2017 13:25:00 -0400

2017 North America User Group traces evolution of newly renamed EcoStruxureFoxboro DCS.



Open system gives precise temperature control

Mon, 18 Sep 2017 19:15:00 -0400

Affinity Energy engineered a universal replacement for cold, warm and freezer chambers at UNC Chapel Hill.



WaTech Israel Water Conference and ICSJWG Conference – Cyber Security Sessions

Sun, 17 Sep 2017 16:08:00 -0400

September 12th, I participated in a cyber security panel at the WaTech Water Technology Conference in Tel Aviv, Israel. One of the focuses of the conference was the “digitization” of water. September 13th, I gave a presentation at the DHS ICSJWG conference on the lack of cyber security and authentication in process sensors. The topic was new to many as most other presentations focused on cyber security of the network.




Surprising Gains from PID Gain

Sat, 16 Sep 2017 17:36:00 -0400

We learned in control theory courses that too high a PID gain causes oscillations and can lead to instability. Operators do not like the large sudden changes in PID output from a high PID gain. Operators may see what they think is the wrong valve open in split range control as the setpoint is approached when PID gain dominates the response. Most tuning tests and studies use a setpoint response rather than a load response for judging tuning. A high PID gain that is set to give maximum disturbance rejection in load response will show overshoot and some oscillation for a setpoint response. Internal Model Control or any control algorithm or tuning method that considers disturbances on the process output will see a concern similar to what is observed for the setpoint response because the load and setpoint change are immediately appearing at the PID algorithm as inputs. There are many reasons why PID gain is unfavorably viewed. Here I try to show you that PID gain is undervalued and underutilized. First, let’s realize that the immediate feedback correction based on the change in process variable being controlled may be beneficial in some important cases. The immediate action reduces the deadtime and oscillations from deadband, resolution and sensitivity limits in the measurement, control valve and variable frequency drive. The preliminary draft of ISA-PCS-2017-Presentation-Solutions-to-Stop-Most-Oscillations.pdf for the ISA 2017 Process Control and Safety Symposium show how important PID gain is for stopping oscillations from non-ideal measurements and valves and also from integrating processes. PID gain does not play as important a role in balanced self-regulating process often shown in control theory courses and publications. The primary process time constant is not very large compared to the dead time. Consequently, there is more negative feedback action seen in these self-regulating processes. When the time constant becomes more than 4 times the dead time, we consider these processes to be near-integrating in that in the time frame of the PID they appear to ramp losing self-regulation. For these processes and true integrating processes, PID gain provides the negative feedback action missing in the process to halt or arrest the ramp. Integrating process tuning rules are used where lambda is an arrest time. Not readily understood is that there is a window of allowable gains, where too low of a PID gain cause larger and slower oscillations than too high of a PID gain. The problem is even more serious and potentially dangerous for runaway processes (highly exothermic reactors). Most loops on integrating and runaway processes have a reset time that is orders of magnitude too small and a PID gain that is an order of magnitude too low. A PID gain greater than 50 may be needed for a highly back mixed polymerization reactor.  Many users are uncomfortable with such high gain settings. For integrating and runaway processes, the PID output must exceed the load disturbance to return the process variable to setpoint. This is more immediately and effectively done by PID gain action. We can often see an immediate improvement in control by greatly increasing the reset time and then the gain. The gain must be greater than twice the inverse of the product of the open loop integrating process gain (%/sec/%) and reset time (sec) to prevent the start of slow oscillations from violation of the low gain limit. As the process variable approaches setpoint, there is an immediate reduction in the PID contribution to the output from the PID gain. Reset has no sense of direction and will continue to change the output in the same direction not reversing direction till the process variable crosses setpoint reversing the sign of the error.  Operators looking at digital displays waiting for a temperature to rise to setpoint will think a heating valve should still be open if the temperature is just below setpoint when in fact the cooling valve should be open to pr[...]



WAGO North America names Toby Thomann president

Fri, 15 Sep 2017 12:35:00 -0400

‘Ultimately, my goal as president is to provide strong leadership and vision to our team, exceed customers’ expectations and provide a great place for our employees to work and achieve their goals,’ he noted.



Ultra-small industrial PCs and reaping industrial IoT benefits

Fri, 15 Sep 2017 12:24:00 -0400

The Industrial Internet of Things is growing rapidly but there is a significant barrier: the substantial number of legacy systems that lack the required connectivity.



Scaled-down DCS for process skids

Fri, 15 Sep 2017 11:39:00 -0400

PK Controller provides a stand-alone process control platform with native connectivity into DeltaV



Time for process automation professionals to evolve

Fri, 15 Sep 2017 10:43:00 -0400

The flashy cuttlefish shows how to handle board-level computers.



Yokogawa Offers Hygienic Gauge Pressure Transmitter

Wed, 13 Sep 2017 15:37:00 -0400

Yokogawa’s hygienic gauge pressure transmitter doesn’t use any type of filling liquid, eliminating the risk of contamination to the process fluid. It is well suited to the requirements of the food, beverage and pharmaceutical industries. It also features quick response, and remote setup and monitoring via HART communication.



Yokogawa Announces New Field Device Maintenance Software

Wed, 13 Sep 2017 15:34:00 -0400

Yokogawa has upgraded its “FieldMate” device maintenance software. This enhanced software provides some functions that support “Pressure Transmitter Calibration” to confirm offline data as “Trend Graph” and “Device Alarm History View” for HART field devices.



Moore Industries Safety Isolators Intended for Digital HART Signals

Wed, 13 Sep 2017 15:28:00 -0400

Moore Industries’ SSX and SST Safety Isolators and Splitters provide reliable isolation and signal conversion for HART data in functionally safe process control settings. Part of Moore Industries’ FS FUNCTIONAL SAFETY SERIES, the two-wire (loop powered) SSX and four-wire (line/mains powered) SST have been certified by exida for...



Moore Industries Delivers Economical and Versatile HIX/HIT HART Isolators

Wed, 13 Sep 2017 15:24:00 -0400

Moore Industries’ HIX and HIT HART Isolators provide highly economical solutions to common and costly problems that plague many of today’s “smart” process loops. Protect and enhance your HART investment with the 2-wire (loop powered) HIX or the 4-wire (line-mains powered) HIT.



FCI Provides New Air/Gas Flow Meters for Large Diameter Pipes/Stacks/Ducts

Wed, 13 Sep 2017 15:19:00 -0400

Fluid Components International’s (FCI’s) breakthrough MT100 Series Multipoint Flow Metersare ideal for optimizing boiler or furnace combustion air feed line flow, stack emissions monitoring (US EPA CEMS compliance), flue gas/scrubber balancing, HVAC duct air flow control and any air/gas flow applications in pipe diameters 20 inches (500 mm)...



Endress+Hauser’s 113 GHz: Best Fit Radar Frequency for Every Application

Wed, 13 Sep 2017 14:19:00 -0400

With the introduction of the Micropilot FMR60, FMR62 and FMR67, Endress+Hauser has completed its portfolio of radar instruments. The new versions, which have been developed as per the IEC 61508 safety-by-design concept, are the first instruments on the market with 80 GHz technology.



Endress+Hauser Offers Analytical Transmitter with Heartbeat Technology

Wed, 13 Sep 2017 14:01:00 -0400

Endress+Hauser’s Liquiline M CM42 is a robust transmitter for pH/ORP, conductivity or oxygen measurement that can be used in hygienic, explosion-hazardous and functional safety applications. Thanks to plug & play Memosens sensors, it is simple to commission and set up.



Application Snapshot: Improving Asset Management

Wed, 13 Sep 2017 13:50:00 -0400

The Industrial Internet of Things (IIoT) is much more advanced than the commercial IoT, primarily due to the prevalence of connected sensors in the industrial world, which are the "things" in the IoT. Hundreds of millions of connected wired and wireless pressure, level, flow, temperature, vibration, acoustic, position, analytical, and...



Enlist today for WirelessHART Bootcamp!

Wed, 13 Sep 2017 13:40:00 -0400

Are you looking to increase your knowledge of WirelessHART technology? If so, you should sign up for WirelessHART Bootcamp, a multi-week online educational program led by FieldComm Group staff and associates. This innovative program will enable enrollees to gain an understanding of topics such as mesh networking basics,...



Latest Registered FOUNDATION Fieldbus and HART

Wed, 13 Sep 2017 13:34:00 -0400

  New Registered Devices       Protocol Manufacturer Type Model / Device Name       HART ABB Flow Meter FCXxxx       HART ABB Automation Products GmbH Mass Flow FCXxxx       HART Anderson Level Transmitter L3       HART Balluff Automation Level Transmitter...



AG-181 System Engineering Guidelines: Industry’s Best-kept Secret

Wed, 13 Sep 2017 13:07:00 -0400

It’s a good idea to rely on an authoritative information source when implementing advanced technology like FOUNDATION Fieldbus. That’s why members of the industrial automation industry turn to FieldComm Group’s AG-181 System Engineering Guidelines for best practices and recommendations for a complete FOUNDATION fieldbus installation, from engineering and design through...



IIoT-based Digitization: FDI and OPC UA Drive Open Information Integration

Wed, 13 Sep 2017 12:36:00 -0400

In the era of the Industrial Internet of Things (IIoT) and Industrie 4.0, device and system integration will be paramount to seamless operation. This article concerns the ongoing collaboration between FieldComm Group and the OPC Foundation to advance open information integration and enterprise data exchange.