Visited Wednesday this plant.
Clean room of 3.200 m², ventilation of 1.560.000 m³/h
12.000 kW cooling capacity.
Class 1 and another part class 1000.
You could eat from the floor or play snooker on it.
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Visited Wednesday this plant.
Clean room of 3.200 m², ventilation of 1.560.000 m³/h
12.000 kW cooling capacity.
Class 1 and another part class 1000.
You could eat from the floor or play snooker on it.
Took +/- 40 pictures of the different machines.
A screenshot from one of the control computers. Can be interesting for some.
I have to make an article of it for the small Belgium HVAC/R magazine Cool & Comfort.
The publisher asked me to make an overal picture of the plant without going to technical.
The plant is in fact to big to write only 3 pages.
It will be written of course in Dutch Marc.
I will post a raw sketch from what I've already written on www.tld-nv.com/refrigeration/Imec2.doc.
It takes 9 Mb due to the high resolution pictures.
Quote:
Originally Posted by Peter_1
Peter, When you write your article on this facility, you might talk about weather they have open protocall,such as LON Works or BACNET with distributed control systems using peer-to-peer communications which are intelligent devices that communicate directly with each other, thus eliminating unnecessary processing through "master" controllers. Compared to master/slave systems, for equivalent control functionality, these communications require less than half the bandwidth for unacknowledged transmission and for acknowledged transmission (the kind required to ensure commands from a keypad controller to a compressor control module, for example), less than one-quarter of the bandwidth is required. Minimal bandwidth congestion and the resulting reductions in sequence of operation (loop) times provide superior system performance, such as speed and accurancy.
Chiller controls today are designed and applied utilizing advancements in computing technology can have significant performance advantages as well. Looking at the case for distributed control within the confines of a single piece of equipment, keeping in mind that from a distributed control perspective such as these York Controllers, Boiler Controllers and fan etc. peer-to-peer communications is the most logical communications scheme and a fundamental element of the distributed control performance advantage today :) .Anyway I should think that the unformed reader would find this of interest
You may consider posting your results on one of the forums for our perusel ;)
LOL Well DAhh? :confused:Quote:
Originally Posted by Marc O'Brien
If you had been educated in physics at the university, you would know what i'm talking about...loser. What did he say,..LOOSER? no, he said loser, as in marc O'Brion :D :D :D Oh, I,m sorry, it's just that your so funny and by the way I wrote a song about you, It's called "I LOVE ME" quite catchy really. Me and my friends get togather swill a few beers, sing your song, laugh and generally have a good time, reading your comedy act material. I'm thinking of writing a poem titled "POOR ME, If only thay could have seen what my friends saw in me ;) ...Where would I be now...a success maybe? :eek: Now isn't that so Americanof me Mr Digital man :(
Now that's REALLY a stupid remark :p comon Mark give up the gost(short verson) and step into the real world :o Tell you what ..If you promise not to call me your hero :cool: ..I promise not to call you stupid!Quote:
Originally Posted by Marc O'Brien
This is just a short excerpt of my published paper:Quote:
Originally Posted by Marc O'Brien
DESCRIPTION OF DIRECT DIGITAL CONTROL TECHNOLOGY
The Iowa Energy Center, (1999), tells us that a Direct Digital Control System, (DDC), consists of a microprocessor-based controller with the control logic performed by software. Analog to Digital (A/D) converters transform analog values into digital signals that a microprocessor can use. Analog sensors can be resistive, voltage, or current generators.
Most systems distribute the software to the remote controllers to eliminate the need for continuous communication capability (stand-alone). The computer is primarily used to monitor the status of the energy management system, store back-up copies of the programs and record alarming and trending functions.
Complex strategies and energy management functions are readily available at the lowest level of the system architecture. If pneumatic actuation is required, it is accomplished with electronic to pneumatic transducers. Calibration of sensors is mathematical; consequently the total man-hours for calibration are greatly reduced. Software and programming are constantly improving, becoming increasingly user-friendly with each update. The three major components for the Direct Digital Control system are the sensor, controller and a controlled device. These three components or, functions, interact to control a medium. For example, air temperature is a controlled medium. The sensor measures the data, the controller processes the data, and the controlled devise causes an action. The sensor measures the controlled medium or other control input, in an accurate and repeatable manner. Common heating, ventilating, and air conditioning (HVAC Sensors), are used to measure temperature, pressure, relative humidity, cubic feet per minute, and carbon dioxide. Other variables may also be measured that impact the controller logic. Examples include other temperatures, time-of-day, or the electrical current demand condition. Additional input information, (sensed data), that influences the control logic may include the status of other parameters.
The controller processes according to Direct Digital Control: A Guide to Distributed Building Automation. (1995); states in part, that the controller processes data that is input from the sensor, applies the logic control and causes an output action to be generated. This signal may be sent directly to the controlled device or to other logical control functions and ultimately to the controlled device.
The control device is a device that responds to the signal from the controller, or the control logic, and changes the condition of the controlled medium or the state of the end device. These devices include, valve operators, damper operators, electric relays, fans, pumps, compressors, and variable speed drives for fan and pump applications. :cool: As i said I teach DDC controls
Yes, fine but back to the original comment,is BACNET or LONWorks intelligent on their own? As I understand them LONWorks cannot talk to BACNET although BACNET can read LONWorks sentences.Quote:
Originally Posted by shogun7
I am intrigued to know how sensors can be calibrated by maths alone. To what is the sensor calibrated to ?
BACnet is a Data Communication Protocol for Building Automation and Control Networks. Developed under the auspices of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), BACnet is now an American national standard, a European pre-standard, and a potential global standard. The protocol is supported and maintained by ASHRAE Standing Standard Project Committee 135.Quote:
Originally Posted by Brian_UK
BACnet is "a data communication protocol for building automation and control networks." A data communication protocol is a set of rules governing the exchange of data over a computer network. The rules take the form of a written specification (in BACnet's case they are also on compact disk) that spells out what is required to conform to the protocol.
BACnet provides a standard way of representing the functions of any device, as long as it has these functions. Examples are analog and binary inputs and outputs, schedules, control loops, and alarms. This standardized model of a device represents these common functions as collections of related information called "objects," each of which has a set of "properties" that further describe it. Each analog input, for instance, is represented by a BACnet "analog input object" which has a set of standard properties like present value, sensor type, location, alarm limits, and so on. Some of these properties are required while others are optional. One of the object's most important properties is its identifier, a sort of numerical name that allows BACnet to unambiguously access it. Once devices have common "appearances" on the network in terms of their objects and properties, it's easy to envision messages that can manipulate this information in a standard way.
LonWorks technology is a communications protocal that provides a solution to the many problems of designing, building, installing, and maintaining device networks: These networks that can range in size from two to 32,000 devices and can be used in everything from supermarkets to petroleum plants, from aircraft to railway cars, from fusion lasers to slot machines, from single family homes to skyscrapers. In almost every industry today, there is a trend away from proprietary control schemes and centralized systems. Manufacturers are using open, off-the-shelf chips, operating systems, and parts to build products that feature improved reliability, flexibility, system cost, and performance. LonWorks technology is accelerating the trend away from proprietary control schemes and centralized systems by providing interoperability, robust technology, faster development, and scale economies. Both Bacnet and Lonworks are "open " protocals where almost any controller mfg's product can be installed. Initially, the choice must be made to install either Bacnet or Lonworks you would not normally have both on a LAN
Brian, If you are familar with Pneumatics you will recall that if you wanted to recalibrate a controller sensor you had to physically go to the controller and reset it's set point, with DDC microprocessors ,however all you have to do is reset the algorithm on the EPROM chip. this can be done sitting at a computer. This is why the process is so fast. To answer the question " What makes these controls 'intellegent" The answer is because of the microprocessor.Within this chip are the brains of all DDCsystems. In the microprocessor, logic and data processing are excuted. The processor generates programmed output for digital and analog control. All sensor signals are processed within the DDC controller and outputare excuted to relays,devices and information systems
Quote:
Originally Posted by Marc O'Brien
Ah Ignorance is bliss, talk about chasing your tail? What the hell are you talking about ...laptops! I'm talking about controllers The process of controlling an HVAC system that involves three steps. These steps include first measuring data, then processing the data with other information and finally causing a control action. These three functions make up what is known as a control loop and that is not a function of a laptop
These three components or functions interact to control a medium. If air temperature is the controlled medium the sensor measures the medium and sends this data to the controller which processes the data and the controlled device causes an action. The intellengce is contained in the form of algorithms in the micropressor(A central processing unit implemented on a single chip). Now you either don't understand the process or your playing more semantic games. But Ha if you need me to teach you DDC I won't do it because you're almost a physicist :rolleyes:
Haven't you forgot the feedback loop?Quote:
Originally Posted by shogun7
On these particular chillers, they are called "intelligent" because they adapt to changes on their own accord (predictive). Rather than a simple on/off procedure as the thermostat. No more, no less. They aren't any kind of artificial intelligence, they simply compute and execute.
Hi Brian
Nice to see you back on the forum :)