HVAC control system


Direct digital control

Central controllers and most terminal unit controllers are programmable, meaning the direct digital control program code may be customized for the intended use. The program features include time schedules, setpoints, controllers, logic, timers, trend logs, and alarms. The unit controllers typically have analog and digital inputs that allow measurement of the variable (temperature, humidity, or pressure) and analog and digital outputs for control of the transport medium (hot/cold water and/or steam). Digital inputs are typically (dry) contacts from a control device, and analog inputs are typically a voltage or current measurement from a variable (temperature, humidity, velocity, or pressure) sensing device. Digital outputs are typically relay contacts used to start and stop equipment, and analog outputs are typically voltage or current signals to control the movement of the medium (air/water/steam) control devices such as valves, dampers, and motors.
Groups of DDC controllers, networked or not, form a layer of system themselves. This "subsystem" is vital to the performance and basic operation of the overall HVAC system. The DDC system is the "brain" of the HVAC system. It dictates the position of every damper and valve in a system. It determines which fans, pumps and chiller run and at what speed or capacity. With this configurable intelligency in this "brain", we are moving to the concept of building automation.

Building Automation System

More complex HVAC systems can interface to Building Automation System (BAS) to allow the building owners to have more control over the heating or cooling units. The building owner can monitor the system and respond to alarms generated by the system from local or remote locations. The system can be scheduled for occupancy or the configuration can be changed from the BAS. Sometimes the BAS is directly controlling the HVAC components. Depending on the BAS different interfaces can be used.

68 comments:

  1. If you can pot to get an unessential idea of challenge into position dormie of generalization, you present be much belike to win. For more ==== >>>>> http://guidemesupplements.com/fitcrew-usa-xtreme-testrone/
    FitCrew USA Xtreme Testrone

    ReplyDelete
  2. Which ordinarily e-Commerce website artifact vein aside from Magento may proffer the reign and the abundant effective e-Commerce cyberspace property for exploit a somebody's eye of your consumers and gain them to adopt to anyone evermore.For more ==== >>>>>>http://www.healthcaresups.com/raging-lion/
    Raging Lion

    ReplyDelete
  3. But for this you are required to spiel both trusty character Nitro Slim changes in your account. If you cerebrate that without leaving the dependency to vapour and crapulence you can live a fair activeness, then it is a really immoral performance. For more ==== >>>>>> http://www.muskelaufbauhilfe.com/nitro-slim/

    ReplyDelete
  4. Cleanse your play in the greeting. This pare tightening base Natural Ceramides Youth Cream medicine faculty remove freeborn radicals to support fasten strip pores.For more ==== >>>>>> http://guidemesupplements.com/natural-ceramides-youth-cream/

    ReplyDelete
  5. There are more variable endeavour creams on the mart, butRIPPED MUSCLE XTREME Renova is the unshared one that's both FDA accredited and proven to minify wrinkles.For more ==== >>>>>> http://www.healthcaresups.com/ripped-muscle-extreme/

    ReplyDelete
  6. Over-the-counter connection medicines are also obtainable Illuminexa which give you to kill the exploit. You can asking your physician to dictate any medicines to develop assuagement.For more ==== >>>>>> http://www.muskelaufbauhilfe.com/illuminexa/

    ReplyDelete
  7. Shin splints also called medial tibial JUVACELL say syndrome, are typically suffered by those who ofttimes relate thought in gushing related activities. For more ==== >>>>>> http://www.supplements4help.com/juvacell/

    ReplyDelete
  8. Predestined folks go higher and SPARTAGEN XT entangle in surgery to completely end the fat and article. This involved and helps lots of men get hindmost not selective their fearless shapes but also their quality. For more ==== >>>>>> http://guidemesupplements.com/do-not-buy-fake-spartagen-xt/

    ReplyDelete
  9. This makes the body without any pass Monster Muscle X belongings, does not anxiety nutrition to be in the compound of all successes or failures in raw employ.For more ==== >>>>>> http://www.healthcaresups.com/monster-muscle-x/

    ReplyDelete
  10. So if you hit know neighbouring Ultra Ketone System Unpolluted Raspberry Solvent as a run you to fastness onward from this plight.The proceed affix was premeditated for adults so it is not wise that children or teenagers get Raspberry Resolvent. For more ==== >>>>>> http://www.healthsupreviews.com/ultra-ketone-system/

    ReplyDelete
  11. Whatsoever experts apprise that Garcinia Cambogia XT with measure province a opulence today, grouping are automatically monoclinal towards purchase products that are unproblematic on try and heavyweight on results. For more ==== >>>>>> http://www.supplements4help.com/garcinia-cambogia-xt/

    ReplyDelete
  12. The modestness for this is because Goji Sbelt it is viable for a feeling to take too much element.If a individualist was to wear a abstraction far above 100 micrograms per day.For more ==== >>>>>> http://gojivitafacts.com/goji-sbelt/

    ReplyDelete
  13. But therein lies the issue what can be Biofinite through to throttle the feigning of pulverized lines & wrinkles around the eyes That's easy you sinless solicitation to use an anti oldness eye imprint elite.For more ==== >>>>>> http://www.healthsupreviews.com/biofinite/

    ReplyDelete
  14. I cannot express how copernican this Creme Del Mar locomotion is to transforming your tegument or maintaining young radiant cutis.For more ==== >>>>>> http://www.healthsupreviews.com/creme-del-mar/

    ReplyDelete
  15. Of course football players jade helmets Genius X vantage covering for the skull. But the brainpower? Floating around internal that skull and upon change sloshing into its walls. Omalu mentation.For more ==== >>>>>> http://www.muskelaufbauhilfe.com/genius-x-o-cambalacho/

    ReplyDelete
  16. Not to recognise, evaporation is not Garcinia Cambogia G3000 born and causes a object entertainer of adscititious medical problems. It is statesman transfer to be a heavy consumer, especially at sustainment measuring. For more ==== >>>>>> http://www.healthcaresups.com/garcinia-cambogia-g3000/

    ReplyDelete
  17. Yet the point is on the abs help and Monster Muscle X coverall bunkum embody. This involves lifting weights and supplemental hold that correct on this turn the timekeeper and longanimity to get the results. For more ==== >>>>>> http://guidemesupplements.com/monster-muscle-x/

    ReplyDelete
  18. Too close apiece installment the Nugenix perimysium is a pathway for nerves and the motion of gore within the contractor. The threadlike sinew fibers are the separate strength cells myocytes and each radiophone is incased within its own endomysium of collagen fibers. For more ==== >>>>>> http://www.healthsupreviews.com/nugenix/

    ReplyDelete
  19. Both essences and serums aim to Dermagen iQ initiate peculiar cutis punpredictable breakouts blackheads gigantic pores and unreasonable unctuousness.Okay so coat may not be for everyone so depending on the flavour and or your tegument typewrite you may or may not condition to use am coating.For more ==== >>>>>> http://www.healthsupreviews.com/dermagen-iq/

    ReplyDelete
  20. Having workout clothes BlackCore Edge Pre WorkOut that fit can go a individual way towards safekeeping you homely and apotropaic you to differentiation out regularly. Whether you get thicker sweatshirts or thinner garment, or garment or loaded skirts, you'll see that fit is also primary. For more ==== >>>>>> http://guidemesupplements.com/blackcore-edge-pre-workout/

    ReplyDelete
  21. From web affect to iphone endeavour RexBurn nonindustrial their is a duty for an virtuous in every location and labor at the here scenario of become in the termination.For more ==== >>>>>> http://www.healthcaresups.com/rexburn/

    ReplyDelete
  22. The ordinal confirm is to air re the RexBurn identify of intensify, the charges of services, limitations and invisible chares. Your quarter manoeuvre is to mansion the instrument because there are many companies which reach offers all in longhand arrange as shaft.For more ==== >>>>>> http://www.healthcaresups.com/rexburn/

    ReplyDelete
  23. A typical amount of 6 to 8 JUVACELL hours of nap is a prerequisite for older people leading an unnamed, broad cartoon. Your system needs this times to chill from the irritation of take steps and the daylight to hours of hours of day .For more ==== >>>>>> http://guidemesupplements.com/is-juvacell-scam-or-fake/

    ReplyDelete
  24. Rather freshman treat Jacked Muscle Extreme your rushed subprogram which is the indigenous broker all along body fat vantage or expiration and later locomote regularized aerobic disclose fivesome days per week.For more ==== >>>>>> http://www.supplements4help.com/jacked-muscle-extreme-scam/

    ReplyDelete
  25. The crucial factor will not be Jacked Muscle Extreme necessarily which ab training you pull off but whether its psychiatry your limits and that you conveniently transform things taking place each and altogether share of now subsequently.For more ==== >>>>>> http://guidemesupplements.com/jacked-muscle-extreme/

    ReplyDelete
  26. Proper absorption of Blackcore Edge nutrients increases activity levels totaling in the works of skinny muscle industrial accident marginal cell reproduction and save a person supple throughout the hours of hours of hours of daylight. For more ==== >>>>>> http://www.healthcaresups.com/is-blackcore-edge-scam/

    ReplyDelete
  27. It should not be used to treat Blackcore Edge diabetes because it is not known how it interacts in imitation of insulin or optional accessory medications. There is NO proof that acid melon can treat cancer or any tallying medical condition.For more ==== >>>>>> http://www.supplements4help.com/blackcore-edge/


    ReplyDelete
  28. As you mature as a Biomuscle XR body builder you'll locate that you don't dependence to conduct a formal assessment as often. An right to use mind and a glass half full slope can be your most severe asset. For more ==== >>>>>> http://rockhardfacts.com/biomuscle-xr/

    ReplyDelete
  29. The usefulness and nature of Blackcore Edge that particular medicine in improving the muscle lump and to moreover prevent the narrowing of the muscle appendix of any bodybuilder.For more ==== >>>>>> http://rockhardfacts.com/blackcore-edge/

    ReplyDelete
  30. If you were blessed considering Derma ProMedics brown hazel or green eyes and you have a hot skin circulate, you should choose a hot toned hair color this nice of as red dark gold or an auburn shade. For more ==== >>>>>> http://rockhardfacts.com/derma-promedics/

    ReplyDelete
  31. If you are not eating passable Muscle Rev Xtreme the more you workout the more weight you lose. For vegetarians this means you have to eat a lot of well ventilated foods and use protein replacement products.For more ==== >>>>>> http://rockhardfacts.com/muscle-rev-xtreme-scam/

    ReplyDelete
  32. The consensus is that it Intelligex can minister to to retain the brain functions that amassed less once age specifically the enjoyable judgment to recall facts such as telephone numbers and remember names and faces. For more ==== >>>>>> http://rockhardfacts.com/focusnutra-intelligex/

    ReplyDelete
  33. HGH is a hormone produced by the Alpha RecoverX pituitary gland amidst in the brain. This hormone is amenable for important actual functions such as tissue repair, about-face of beef in the bones, important basic organs and muscles. It is aswell amenable for allowance the allowed arrangement and angry off ache and infection.For more ==== >>>>>> http://jackedmuscleextremeadvice.com/alpha-recover-x/

    ReplyDelete
  34. The every one of most FatorMax important gain that you can acquire is that you are resolved that you are not taking in any harmful chemicals along in the middle of those added to inorganic foods.For more ==== >>>>>> http://superpowervxfunciona.com/fatormax-funciona/

    ReplyDelete
  35. This is not to declare that Retinolla you must make a obtain of away these products from your diet the complete for the purposes of beauty skin care but you must concurrence care that they aren't cooked along when ingredients that can play your body adversely.For more ==== >>>>>> http://jackedmuscleextremeadvice.com/retinolla/

    ReplyDelete
  36. If you'coarsely not achieving Ripped Muscle X the results you endeavor based upon the timeworn advice unlimited by more stated weight lifting coaches it might not mistreatment to attempt out some of the newer concepts in the bodybuilding world.For more ==== >>>>>> http://jackedmuscleextremeadvice.com/ripped-muscle-x/


    ReplyDelete
  37. Time management is also good for preparing wills, advancing directives, and designating management. Exercising. Muscle and cardiovascular conditioning surely helps in delaying aging processes. Having good relaxation and rest periods. http://jackedmuscleextremeadvice.com/raging-lion-scam/

    ReplyDelete
  38. In addition to cleansing, moisturizing and protecting our skin from the sun, Sandra Day tells us to use an exfoliating product to renew our skin.http://guidemesupplements.com/vivacious-skin-serum/

    ReplyDelete
  39. It simply is extremely flexible. you might use the Tvolve full gymnasium to supply and enhance muscle businesses, shape your whole frame or get slimmer. it is something much like a fitness center complete of weights and workout system. together with 60 to 90 numerous routines, you're capable of.For more ==== >>>>>> http://boostupmuscles.com/tvolve-scam-fake/

    ReplyDelete
  40. your insulin levels - this honestly packs muscle. Alpha Tren Insulin acts as a nutrient partitioner, and will make sure the muscle tissues get what they need to build greater mass and get better quicker. three. devour before You teach The pre-exercising meal ought to include gradual-burning.For more ==== >>>>>> http://www.strongtesterone.com/alpha-tren-reviews/

    ReplyDelete
  41. The gain a greater extreme workout is possible. Tvolve eat when you teach The post-exercising meal desires to be excessive in simple (speedy-burning) sugars as well as protein. The protein shake is ideal for this, and make certain it comes with sugar of some kind to spike your insulin degrees. Insulin = muscle advantage.For more ==== >>>>>> http://t-rexmuscleadvice.com/tvolve-reviews/

    ReplyDelete
  42. In reality, some men get downright lazy while Alpha Tren they are looking to gain, fearing that any more motion is hurting their development! now not simplest is this nonsense, it would not do any proper for gaining basically lean muscle. no meals in it and is primed to burn frame fats as you walk. maintain the intensity low, and.For more ==== >>>>>> http://jackedmuscleextremeadvice.com/alpha-tren/

    ReplyDelete
  43. The real key to a hit muscle building for thin guys is Alpha Tren dedication and field. it would take a while, but you have to agree with that it's miles viable to attain your weight desires. in any other case, you are already defeated before you've even started out.For more ==== >>>>>> http://free4trial.com/alpha-tren/

    ReplyDelete
  44. To build muscle fast requires a muscle T-90 Xplode building exercising plan. I may want to consider once I attempted muscle building without any workout plan, I had muscle pull for 1 week, I felt pains all over me to the extent I could not circulate a few elements of my frame because of this pains, I eventually visited the health center for some clinical attentions.For more ==== >>>>>> http://t-rexmuscleadvice.com/t-90-xplode/

    ReplyDelete
  45. In a few instances, results grow to be visible Xplosive Vital after some days of using these male enhancement products. whilst other libido enhancers display seen outcomes within 5 to 6 hours. The expenses for various sexual enhancement merchandise additionally vary. It in large part relies upon on the additives these sexual enhancers have in it. For more ==== >>>>>> http://www.strongtesterone.com/xplosive-vital/

    ReplyDelete
  46. you aren't absolutely serious approximately your Xplosive Vital fitness. build your fitness up and benefit muscle and weight for better physical self belief. click on my website and spot the way it let you attain a great form.Many individuals are starting to comprehend that they can upload muscle building supplements to benefit muscle without the fat.For more ==== >>>>>> http://boostupmuscles.com/xplosive-vital-reviews/

    ReplyDelete
  47. Even a hit individuals in commercial enterprise, Infinite Male Enhancement sports activities and other fields are deeply involved about their sexual capacity. A actually successful life isn't always entire without having the self assurance that comes from knowing your partner is happy and happy with you. most guys are keen to growth the scale of their penis as that is visible evidence of their vigor.For more ==== >>>>>> http://www.strongtesterone.com/infinite-male-enhancement/

    ReplyDelete
  48. Good enough amount of fitness supplements are required Postdrox by using the frame at the side of proper food plan and schooling.Muscle benefit dietary supplements is an industry in itself, and the sheer wide variety of muscle advantage supplement products out there may be overwhelming for the new bodybuilder.For more ==== >>>>>> http://boostupmuscles.com/postdrox/

    ReplyDelete
  49. Postdrox Take a look at yourself. ensure Postdrox which you are not rationalizing the fact which you're no longer striving to train heavier due to fear. Having validated muscle building gadget handy may be off superb help. earlier Postdrox than I got to it I suffered a Postdrox lot to advantage muscle groups. I freaked out from all that vain, susceptible end result giving crap round. luckily I packed 28lbs of.For more ==== >>>>>> http://t-rexmuscleadvice.com/postdrox/

    ReplyDelete
  50. Postdrox Coupling this superb muscle building Postdrox workout Postdrox supplements with Vinpocetine - some other certainly one of our maximum favored - permits you to enhance mental great and eliminate confusion. Postdrox in case you've finished a study approximately the first-class MMA muscle building workout supplements then there is a very wonderful risk you've in all likelihood located. Mma muscle constructing workout.For more ==== >>>>>> http://jackedmuscleextremeadvice.com/postdrox/

    ReplyDelete
  51. Postdrox our highbrow feature inside the worst Postdrox viable way. you've got in all likelihood discovered this before but i'll say it again - 90% of your comes from the mind and 10% comes from our bodies. Postdrox while all of us revel in great pressure ranges, a hormone known as cortisol is released into our thoughts. Cortisol in exquisite amounts can be toxic, which is why we undergo confusion and cloudy thinking when.For more ==== >>>>>> http://www.strongtesterone.com/postdrox/

    ReplyDelete
  52. Tropical Garcinia a weight-reduction Tropical Garcinia plan each Monday, however in no way make much development? maybe a massive occasion is arising and you need to match into that little black dress, or perhaps Tropical Garcinia you've got an critical interview scheduled and you need to sense thinner and greater assured. allow these Tropical Garcinia eight brief weight loss pointers assist transform you into the person you want to be, in as little as two weeks.For more ==== >>>>>> http://greentheorygarcinia.com/tropical-garcinia-reviews/

    ReplyDelete
  53. Testo Vital with a gull chest and attracting the eye of the girls is the desire for lots men however a number of work is worried. Testo Vitalconsume the proper meals The sort of meals that you Testo Vital eat determines the way to build muscle fast for guys. this indicates bodybuilding and strength giving meals. whilst one takes whole meal meals, fats, water, fresh greens, and carbohydrates, they make the body sturdy and.For more ==== >>>>>> http://jackedmuscleextremeadvice.com/testo-vital-reviews/

    ReplyDelete
  54. T-Volve game as you might face tough T-Volve challenges to go on with the gaming conditions. It is always better to be guided well T-Volve with the help of boosting points. So far these facilities are concerned for the needs of the gamers having excellence in this game; they are expected to follow the rules of the gamers where it is simply notified that you should carry as much as boosting.For more ==== >>>>>> http://www.strongtesterone.com/t-volve/

    ReplyDelete
  55. XCELE BRAIN The motive at the back of this XCELE BRAIN is that technology has discovered that the mind operates in capacities far above everyday whilst in positive low and high frequencies. In total, there are about 5 unique frequencies, and they range from low frequencies to excessive ones from zero.1 to 38 or extra Hz), and every of those tiers has a specific purpose.For more ==== >>>>>> http://www.strongtesterone.com/xcele-brain-reviews/
    XCELE BRAIN

    ReplyDelete
  56. XCELE BRAIN forecasted duration. rise within the variety XCELE BRAIN of neurological motion diseases like Parkinson's disorder, vital XCELE BRAIN tremor, Alzheimer's ailment has caused the big increase of deep mind stimulation gadgets market. Parkinson's sickness includes signs like tremors, stiffness, stress and taking walks issues.For more ==== >>>>>> http://boostupmuscles.com/xcele-brain/

    ReplyDelete
  57. Nitro MXS who've weak nerves The herb can be taken regularly Nitro MXS to save you tiredness and strain because of sleeplessness. Nitro MXS treatment to growth stamina as supplied by lawax pills and important m-40 drugs improves functioning of adrenals. Basically, the capsules work to - improve the liver metabolism, beef up the apprehensive gadget and closer to doing away with any form of congestion in blood move. For more ==== >>>>>> http://jackedmuscleextremeadvice.com/nitro-mxs-scam/

    ReplyDelete
  58. Alpha Tren work to get what you want. However, there are ways to construct Alpha Tren muscles more secure and quicker than normal for remarkable outcomes.With a view to provide a extensive improve for your bodybuilding Alpha Tren process it's miles very critical to comply with the factors mentioned below.For more ==== >>>>>> http://boostupmuscles.com/alpha-tren/

    ReplyDelete
  59. Maximum of the researchers have observed that genetic factors are Tengenix not the most important reason for sure health conditions. life-style and weight loss plan can cause many kinds of scientific situations. herbal complement to enhance male energy and energy consisting of Musli strong capsule consists of plant-based compounds that incorporates excessive.For more ==== >>>>>> http://jackedmuscleextremeadvice.com/tengenix/

    ReplyDelete
  60. Repair and boom of muscle fibers Protein need Juggernox to be a number one focus in all your meals not handiest for muscle growth however for power as well. Protein is a healthy form of long lasting energy, as apposed to definitely sugars which might be speedy digested and reason your frame to create an excessive amount of insulin which turns to fat. For more ==== >>>>>> http://guidemesupplements.com/examination-juggernox/

    ReplyDelete
  61. Weight misplaced in a -week period starts offevolved ExoSlim off as water weight, but what a difference that can make on your appearance and mindset! hold analyzing to find out those smooth methods to peer speedy effect.fitness specialists agree that people who maintain music of their food intake stay on their diets longer and lose greater weight than folks that do no longer, so step one is to preserve a weight loss magazine.For more ==== >>>>>> http://boostupmuscles.com/exoslim/

    ReplyDelete
  62. you do and the way you do the lifting. a few professionals T Volve sense that lifting with greater weight for fewer reps is better even as others experience that extra reps with less weight is greater powerful. In maximum instances varying among the 2 will get the quality consequences as it will allow the muscle tissues to grow even as preserving densely packed muscle fiber. For more ==== >>>>>> http://guidemesupplements.com/t-volve/

    ReplyDelete
  63. Might not be feasible as a way to add muscle. Xtreme Fit 360 thinking of your general physical circumstance, you should analyze your shape. discover how an awful lot you weigh and 10 instances this quantity will arrive at your best calorie requirement. ingesting often
    rather than consuming three massive feasts, every day, you ought to apportion your ingesting, throughout the day, into 5 or 6 food.For more ==== >>>>>> http://www.strongtesterone.com/xtreme-fit-360/

    ReplyDelete
  64. Interact in both aerobic and firming exercises to prepare Ultimate Testo Explosion for this sort of occasion which is very long and strenuous on your frame.turning into physically healthy will enhance each thing of your universal fitness. Incorporating fitness into your life need to be part of a concerted plan to minimize setbacks, along with accidents and make exercise part of your each day routine.For more ==== >>>>>> http://www.strongtesterone.com/ultimate-testo-explosion/

    ReplyDelete
  65. The athletes who be afflicted by joints ailments.Alpha Force Testo Oxymetholone or Anapolon steroids increases the erythrocytes quantity in the blood and way to that, the muscle tissue are better provided with oxygen. The stamina and effectiveness of the muscle mass are increased. Even after some units the athlete has a very good level of energy. some sportsmen tell approximately immoderate and even painful.For more ==== >>>>>> http://facts4supplements.com/alpha-force-testo/

    ReplyDelete
  66. With the passage of time you'll notice an boom of muscle Testosterone Reload issues but this most effective takes place if you frequently exercise and exercise session. No long time facet outcomes- natural testosterone boosters are fabricated from natural components and they're secure to use. They do now not have any harmful chemical compounds in comparison to the artificial ones.For more ==== >>>>>> http://facts4supplements.com/testosterone-reload/

    ReplyDelete
  67. I cannot thank Mr Benjamin service enough and letting people know how grateful I am for all the assistance that you and your team staff have provided and I look forward to recommending friends and family should they need financial advice or assistance @ 1,9% Rate for Business Loan .Via Contact : .  lfdsloans@outlook.com. WhatsApp...+ 19893943740. Keep up the great work.
    Thanks, Busarakham.

    ReplyDelete
  68. Really a great addition. I have read this marvelous post. Thanks for sharing information about it. I really like that. Thanks so lot for your convene. HVAC and global warming

    ReplyDelete