e.r.i.c. technical section 2006 archive/flow control... · 2009. 8. 31. · technical section-----...

e.r.i.c. TECHNICAL SECTION 2006

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Introduction to e.r.i.c.The compulsory ventilation inspection (OVK) which, accordingto Swedish law, must be carried out on ventilation systems atregular intervals has during the last decade provided us witha good picture of the status of our ventilation installations. Inmany cases the results have been astonishing and give us areason for reflection. It can be established that most ventila-tion installations do not conform to the demands that wereonce made on them, see figure 1.

Figure 1. Compilation of 5000 different OVK systems.

It is evident from the diagram that the most basic systems (S)showed the worst results while the more complex (FTX)showed the best results. One explanation for this can be theFTX systems are newer than the other systems and above alloffices are equipped with some form of cooling function.Maintenance personnel probably hear immediately if the cool-ing does not work. Despite this the diagram still illustrates thatonly about 50% of the FTX installations were approved.

Reasons for the problemThe reasons for the deficiencies vary, but the most importantreasons for impaired function are:• Imbalance has occurred in the system due to it being sensi-

tive to different types of disturbances. You could say that the system is not “forgiving” but is affected by distur-bances instead of being corrective. Consequently, insuffi-cient air flow rates can occur in parts of the system while in other parts the air flow becomes too large resulting in troublesome noise and draughts.

• System maintenance has been neglected, which affects operating reliability.

• Activities have changed and the original air flow rates are not good enough for the new activities.

• Trimming has not been carried out correctly or according to the changes in activities. Frequently systems are also designed with a constant air volume, which does not always permit a change in the air flow.

Insufficient air flowIndividuals consume approx. 350,000 kg of air during theirlifetime. This can be compared with the intake of solid nour-ishment, which is a fraction of the amount of air.In an investigation by the National Swedish Institute of PublicHealth it was discovered that we have experienced a doublingin allergy problems every 10th year since 1960 and currentlysome 40% of our children in infant schools suffer from someform of allergy. The fact that this is purely due to ventilationand air flow is probably not true, but that there is a link be-tween too small air flow rates and allergies is probably obvi-ous. To transport any contamination in the room air outrequires at least that correctly designed air flow rates aremaintained.

Figure 2. Distribution of a total intake of 350,000 kg air. 6and 7 inserted in the diagram for comparison.

Noise and imbalanceNoise is one of the most common problems associated withventilation installations. One reason is because a too largepressure drop in the final nozzle and adjustment damper arepermitted. Today, both the products and know-how exist toprevent these problems. Despite this it is not unusual for usersto solve the problems themselves. Manipulating the ventila-tion installation by blocking a nozzle causing noise or adraught is not an unknown solution. The problem is thensolved in the room in question, yet it is only really moved toother parts of the system. In the worst scenario if this happensin several parts of the system the entire installation will be-come imbalanced.

EnergyInvestigations show that approx. 40% of all energy producedin Sweden is used to supply our buildings with requisite ven-tilation, cooling and heating. Many ventilation installationscurrently run with a constant flow, despite the load varying.The call for demand controlled solutions will in all probabilitygrow with the increase in energy costs.

Demand controlled air flowBy tradition many ventilation installations are designed with aconstant air volume, which is controlled at given operating

S = Natural draught systemF = Exhaust air systemFT = Supply and exhaust air systemFTX = Supply and exhaust air system with recovery

1 Tenement building2 Office3 Schools

1. Air in the home 5. Air when travelling2. Air in public buildings 6. Fluids3. Air in industry 7. Solid nourishment4. Outdoor air

3SWEGON e.r.i.c. 2003 - Rev. 1 February 2006

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Technical section ------------------------------------------------------
times. Irrespective of the load in the premises a constant airvolume is delivered During the last few years the interest incontrolling the air flow to match the need in the premises hasincreased, which opens the door for new solutions within thisfield. Traditional solutions employing VAV systems have beencriticised as they require extensive service and maintenance,as they are frequently fitted with dynamic pressure sensorsthat can be blocked by contamination and thereby lose theirfunction. Future solutions within this field will require prod-ucts and systems offering high reliability and a minimum ofservice and maintenance.
Future demans and solutionsThe vision of tomorrows’ ventilation system that satisfiesman’s demands, both expressed and implied, is of a systemthat can be adapted to the needs of the individual at differenttimes. In addition the following demands should be made:• Noise problems caused by the ventilation system are to be

eliminated.• Imbalance should not be created by changes or by the

effects of external factors.• Simple trimming is facilitated in both new constructions

and conversions.• Flexibility to change for different activities and demands.• Operating costs minimised through demand controlled air

flow.


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e.r.i.c. systeme.r.i.c. system is an acronym for Easy and Reliable Indoor Cli-mate. The starting-points when developing the system havebeen reliability, operating safety and economy, as well as thatthe system should be characterised as a comprehensive solu-tion. The system does not differ dramatically from a conven-tional system without the possibility of individual control.However, one basis where the e.r.i.c. system does differ froma conventional system is that the system has been designed tomaintain a constant pressure in branch ducts via branch ductdampers.

Basic philosophyThe basic idea of the e.r.i.c. system is that the flow require-ment should be controlled in the room and that the systemshould adapt itself according to this with as low energy con-sumption as possible. This means that each room can live itsown life and, for example, direct control (i.e. half the flow atthe weekend and other time-based control) of the flow in theunit becomes redundant. There are three reasons to vary theflows to the different rooms:

• Comfort. If under tempered air is used to create the required room temperature, the flow is varied depending on the thermal loads. If the personal loads in the room vary, the flow can vary, to ensure the air quality.

• Energy. If only half the class are in the classroom or if only half of the office is manned, it is sufficient to ventilate for half the personal load. By only ventilating when it is needed saves the energy for fans, heating and cooling.

• Noise. The higher the air velocities the more noise gener-ated from the fans and duct system. By not running at maximum flow to all the rooms, the air velocities and pres-sure rises in the system are reduced, which gives lower noise generation.

Figure 3 illustrates an e.r.i.c. system where the unit transportsthe air to the branch ducts, which have a constant static pres-sure. The constant pressure means that the flow can vary outto the different rooms without flow measurement and with-out flow variation in one room affecting another. The flow inthe room can be controlled based on the cooling requirement,carbon dioxide content (CO2) or presence. Combinations withcontrol of lighting, cooling and heating valves are also possi-ble.

Figure 3. Typical e.r.i.c. system.1. System Manager KSM2. Pressure sensor for the unit’s pressure control3. Zone Manager KZP/KZM4. Slave controller KSA5. Room Manager KCD/KCW


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TRADITIONAL GROUPING OF VENTILATION SYSTEMSThe choice of an appropriate technical solution is an impor-tant step in planning. System selection ought to be madebearing in mind the following four main factors:
Suitability. The ability of the technical solution to satisfy thequality demands imposed.

Operating reliability. The ability of the technical solution toprovide long-term satisfactory operation.

Resource economy. The technical solution’s energy efficien-cy, cost efficiency, etc. When selecting the technical solutionyou should always seek simplicity, intelligibility and toleranceagainst deviations in operating conditions. Avoid technical so-lutions that do not permit room usage to be changed, win-dows to be opened or in any other way is sensitive to externaldisturbances.

Basic principles and characteristic propertiesThere are different ventilation engineering solutions that canmeet the demands of correct air flow to all parts in a system.The main categories discussed are:• CAV system (Constant Air Volume), system with constant

air volume. The most basic and in general most “inexpen-sive” option.

• VAV system (Variable Air Volume), system with variable air flow, which is generally controlled via a room thermostat. The fan is equipped with some kind of pressure regulation.

• DCV system (Demand Controlled Ventilation), requirement control of the air flow, which is generally controlled via an air quality or presence detector.

• Naturally all system solutions can be designed with either mixing or thermally controlled ventilation (displacement ventilation).

CAV as well as DCV systems can be combined with optionalheating and cooling equipment for controlling the room tem-perature.

Figure 4. Principle of a CAV system.1. Exhaust air2. Supply air3. Ventilation unit (FTX)


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CAV systemThe CAV system is used where both heat generation and con-tamination production are low and fairly constant. The supplyair flow is primarily determined by the air quality demands. Ifthe hygienic air flow to transport away the heat is not suffi-cient, you can supplement with products for waterborne cool-ing. Disadvantages: CAV systems are usually based on thebranching principle with adjustment dampers in each branch.The pressure drops across the terminals are selected so thatwhen combined with the pressure drops across the adjustabledampers they give the right flow distribution.The disadvantage of this principle is that the system can easilybecome imbalanced due to disturbances from thermal risingforces, changes of damper positions, etc. Further disadvantages are the relatively high pressure dropacross the damper and terminal necessary to ensure that theflow variations do not become too high. This in turn can resultin the noise problem becoming an inconvenience at the sametime as energy consumption becomes unnecessarily high.A lowering of the fan speed, in order to reduce energy con-sumption during specific periods, means that the flow distri-bution cannot be upheld, because the pressure drop acrossthe terminal and damper decreases.

VAV/DCV systemUsed when the personal load varies. Radiators are an appro-priate heating method. The room’s cooling requirement is ad-justed using a variable air flow.Disadvantages: The VAV/DCV systems differ from the CAVsystems among others through pressure regulation on themain ducts for the supply and exhaust air. This is necessaryfrom both energy and noise points of view.Another difference is that in the immediate connection to thesupply air terminal devices there are controllers that controlthe air flow rate through the terminals. A basic problem withthis is, as the flows are reduced, the pressure drop increases.This can have serious consequences. An increased pressuredrop generally creates higher noise levels. The pressure in themain ducts must guarantee the whole time that the worst po-sitioned branch duct receives sufficient air.If the flow distribution in the system allows a temporary lowerpressure, the set point value must still be maintained. Natural-ly this has a negative effect on the operating costs.

Figure 5. Principle of VAV system.1. Exhaust air2. Supply air3. Ventilation unit4. VAV unit


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NEW SYSTEM SOLUTIONSInterest in new ways of constructing ventilation systems is in-creasing. The reasons for this are several:1. System solutions have not permitted simple trimming.
This has resulted in system imbalance with subsequent high pressure drop in specific parts and with that too high noise levels. In other parts of the system the air flow rate has been too low resulting in impaired air quality.

2. A low installation cost has been prioritised when plan-ning of the unit. The consequence of this has been units that are too small with high noise levels resulting in noise problems.

3. Imbalance usually occurs between the supply and exhaust air. Imbalance in the building causes pressure differences with the surroundings, which results in increased energy costs and damage to the facade.

4. Consideration to the user’s wishes. As a user you what to influence your climate.

5. An important aspect today is also to keep down energy consumption. In Swedish buildings about 40% of all energy produced is consumed solely to provide them with ventilation, heating and cooling. It is therefore necessary to put together system solutions that can minimise energy consumption without forgoing comfort. In the light of experience available, not least from the compul-sory ventilation inspections, we can easily describe the demands we should make on modern climate systems.

Demands on new system solutions:1. System designs so that these accept the normal distur-

bances that always exist in our surroundings, a.k.a forgiv-ing system solutions.

2. System designs so that traditional trimming work is elimi-nated and assurances are given that the design flow can also be maintained.

3. System designs so that energy consumption can be mini-mised.

4. System designs so that the risk of noise disturbances are minimised.

5. System designs that are flexible so they can be easily adapted to variable activities.

6. System designs so that there is always a balance between the supply and exhaust air flow rates.

7. System designs so that individual regulation of the tem-perature and air quality is given priority.

8. System designs that eliminate draught problems when the air flow is requirement controlled. In order to satisfy these demands an important part of our new system solution, e.r.i.c., is that we maintain the static pressures constant at an appropriate position in the branch ducts. Pressures are not set higher than necessary to produce the planned air flow rates.

Can all of these demands be satisfied? Yes, by using a systemthat maintains the pressure constant all the way out to thebranch ducts!

Why pressure control?By maintaining the pressures constant on the branch ductsconditions are created for:1. Flexible installation. Individually, variable air flow rates can

be achieved without jeopardising the balance in the sys-tem. Terminals for constant and variable flows can be mixed without problem on the same branch duct.

2. Silent installations due to optimal low pressure drops in both the main as well as branch ducts.

3. Energy efficient installations as no extra pressure drop occurs to assure the air flow rates.

Figure 6. Relative energy consumption depending on thetype of system.1. Relative energy consumption fan %2. Relative air flow requirement %


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LCC ANALYSISLife cycle cost (LCC)A ventilation system involves different costs, which occur atdifferent times during the system’s life span. These costs arecollectively known as the lifecycle cost. Since the installationcost is only part of the lifecycle cost it is often better to chooseand dimension a system based on the lifecycle cost ratherthan just the installation cost.The costs associated with a ventilation system are the installa-tion cost, which consists of material and labour, annual ener-gy costs, annual operating and maintenance costs, possiblerenovation or conversion and scrapping.All costs in a LCC analysis are converted to today’s value ac-cording to the following method.

TheoryThe following formula is used to calculate the current value offuture costs, where Cinst is the installation cost, Cyearly is thecost incurred each year for n years (e.g. power and mainte-nance costs), Ci is one or more one-off costs that crop up afteri years, and r is the discount interest rate.

The chart on the right shows one example of how the lifecyclecost may be broken down for a modern office building in cen-tral Sweden with chilled beams and a CAV system. The totalair handling cost is roughly SEK 2,200/m2 over the lifetime,which is assumed to be 20 years.

e.r.i.c.One of the purposes of the e.r.i.c. system is to reduce the an-nual energy requirement and in doing so reduce a large partof the LCC. As the system has more complicated control thanconventional systems the maintenance costs increase, yet thisis counteracted by less trimming and improve flexibility.

Research projectSwegon AB is involved and supports a research project inves-tigating LCC analyses for different climate and ventilation sys-tems. As this project progresses the result will be presented onour website.

Figure 7. Spread of costs in a typical office block with a CAVsystem supplemented with chilled beams.1. Waterborne climate installation2. Air conditioning plant3. Maintenance4. Energy


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e.r.i.c. SYSTEMThe system can be divided on the following three levels.
System levelSystem level concerns the System Manager that communi-cates with the branch dampers and the units to optimize thepressure after the fan so that the fan always runs at the lowestpossible speed to give as low energy consumption and noisegeneration as possible.

Zone levelZone level concerns constant pressure control in the branchducts. Also included on the zone level is the slave control ofthe exhaust air.

Room levelRoom level concerns control of the indoor climate. This con-trol is done with an active terminal, room controller and enroom unit. Waterborne products, radiators and preheatingbatteries can also be controlled by using the room controller.Control can take place based on temperature, presence andCO2 concentration.

ENERGY OPTIMISATION WITH e.r.i.c.System level

The concept of the Swegon e.r.i.c. system is based on pres-sure control in the branch ducts where a constant pressure ismaintained at pressure sensor points, for example, at approx.35 Pa. The control damper at the beginning of the branchducts handles pressure regulation. The System Manager is acontroller that communicates (LONTALK®) with the branchdamper and the unit. Optimisation is achieved through theSystem Manager keeping track of the damper positions andminimising the unit’s rise so that at least one of the damperson the supply respective exhaust air sides is always nearly fullyopen irrespective of the operating mode. The system also al-lows energy optimisation on very small installations at a rea-sonable cost. The System Manager and unit can alsocommunicate with other central units in the building, for ex-ample, so that pumps and supply temperatures in the heating/cooling system can be adjusted for minimal energy consump-tion. In this way energy is saved and noise disturbances areeliminated by the unit always running at as low a speed aspossible.

Night coolingTo save cooling energy you can utilize the lower outdoor tem-perature at night to cooling the carcassing. The night coolingfunction is easily achieved through a controller or a mastersystem sending a command to the rooms for night cooling.The terminals are then opened to their max-positions and amax-flow is obtained until the signal for normal operations issent from the master system.

Around the clock operationNo control of the unit for night or day operation is needed, asflow control is managed out in the rooms. If no one is presentthen automatic mini-flow is used in all rooms and whole sys-tem runs at low speed. With no presence the flows can be re-duced to a minim flow and the SFP value is reduced by 88%.Accordingly, fan energy is in principle negligible in this oper-ating mode. During the night the fans should not be switchedoff for reasons of hygiene. The motive for this is quite self-ev-ident:1. You should, due to the building emissions, have a purify-

ing air flow even during the night.2. The fans must be running to avoid contamination from

entering the duct system due to back draught.

Figure 8. The e.r.i.c. system.1. Exhauxt air2. Supply air3. System Manager4. Zone Manager, branch damper


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Heating batteryIn winter the air flow is not controlled to the same degree bythe cooling requirement and can therefore be regulated downto a minimum flow, which with the e.r.i.c. system can be aslow as 20% of the maximum flow. When active terminals areused it is no problem to supply a minimum flow with subnor-mal temperatures of up to 12K. At such low flows a rotatingheat exchanger has a temperature efficiency of over 80% (uptowards 85%). This means that the supply air temperaturecould be 14°C at -22°C outdoors (23°C on the exhaust air).You should consider the cost of installing and maintaining aheating battery.

UnitUnits with a large flow range should be chosen for the e.r.i.c.system. The unit should be equipped with pressure control ofthe fans. When the System Manager KSM is used the unit’spressure control should have LON communication with KSM.It is recommended to use an outdoor temperature compen-sated supply air temperature with the e.r.i.c. system.

Supply air temperatureAs all room controllers can communicate the system containsavailable information about the size of the cooling or heatingrequirement in all rooms. This gives the possibility of selectingthe most optimal supply air temperature so that:• the heat exchanger is utilised to full in heating instances• free cooling is always utilised instead of increased flows in

cooling instances• the supply air temperature is not lower than necessary in

summer instances.

Zone levelThe system composition with constant static pressure inbranch ducts contributes to low noise levels and energy con-sumption. As the system is always in balance infiltration is re-duced. See figure 9.

Room levelThrough only ventilating when and where there is a need en-ergy can be saved and the noise level; from the duct systemand fan are reduced. The need is controlled directly from theroom. If no one is there only the set minimum flow is supplied.The presence detector can also be connected via the roomcontroller to the lighting. See figure 10.

RadiatorsThrough both controlling the air and radiators with the roomcontroller the risk of simultaneous heating and cooling is elim-inated.

Window contactIf a window contact is connected to the room controller theroom ventilation is switched off when a window is opened.Energy can be saved by not supplying air via the ventilationsystem if the user has chosen to air the room by opening thewindow.

Figure 9. Zone/branch level. Separate constant pressure onthe supply and exhaust air.1 and 2. Pressure sensor KSP3. Branch damper

Figure 10. Room level. With active supply and exhaust air ter-minals the balance between the supply and exhaust air is con-trolled on a room level. Branches on the supply and exhaustair only need to maintain a constant static pressure. No flowmetering is necessary.1. Exhaust air terminal2. Supply air terminal3. Regulator4. Room unit KST


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ACTIVE SUPPLY AIR TERMINALFlow control on the supply air
By maintaining a constant pressure in the branch ducts flexi-bility is created with regard to the changes in flow in the ter-minal. The terminals can be changed individually without thishaving a negative effect on the balance in the system or theunit’s trimming. Unlike VAV units, no flow metering in the ter-minal is necessary, which results in reduced maintenance anda stable system. The flow is determined based on the termi-nal’s opening (between 0 to 100%) and the underlying con-stant static pressure. Maintaining a constant pressure istherefore motivated even if the installation is designed to op-erate as a CAV system. The installation automatically compen-sates for the “disturbances” that always occur in systems.Consequently, maintaining constant pressure allows the ter-minals with constant and varying flows to be combined onone and the same branch. See figure 11.

Figure 11. Characteristics for a supply air terminal device in abranch with constant static pressure. Unlike systems with var-ying pressure the noise level decreases here with the reducedflow.


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Constant outlet velocity - no draught problemA prerequisite to obtain a good distribution pattern in a room,when heated or chilled air is supplied, and when the air flowvaries within a large flow range, is that the supply air velocitywhen it leaves the terminal is constant. This can be easilyachieved through flow regulation taking place in the terminaloutlet instead of its inlet. A prerequisite for this is that thepressure is constant in the branch duct. The “disturbances”that occur in the form of varying air flow is automatically com-pensated for through maintaining constant pressure in thebranch duct. Products that are especially suitable to use forconstant outlet velocity are circular or square single cone dif-fusers. Nozzle terminals normally have good properties withvarying air flow. The lowest permitted air flow with a subnor-mal temperature of approx. 5°C is however normally limitedto about 30% of the maximum air flow. If you want to furtherreduce the air flow a terminal with a constant outlet velocityis required.Remembering that you want to establish a uniform distribu-tion pattern in the room, the outlet velocity must be fairly con-stant when the air flow varies. A reduced outlet velocitymeans that it is easier for the air to release from the ceilingand drop down to the occupied zone resulting in increasedspeed. A distinction is made between two types of supply airterminal device:1. Passive terminals that have the same setting independent

of the air flow.2. Active terminals that have flow regulation in the terminal

outlet, which gives a constant outlet velocity independent of the air flow.

If, using passive terminals, you reduce the air flow from 100%to 30%, the throw length is also shortened by 30%. If you re-duce the flow in the same way with an active supply air termi-nal device, i.e. a terminal where the outlet velocity ismaintained constant through the outlet area changing, thethrow length will be 55% of its original length. The reductionis in no way a problem for any of the terminal variants as theair does not release its contact with the ceiling due to the highoutlet velocity. Air flow rates also become lower. The flowpattern out into the room is similar to the flow pattern withthe larger air flow, but with a smaller penetration depth.The major differences between the passive and active termi-nals are:1. the draught risk increases with a passive terminal as the

air flow decreases.2. the draught risk decreases with an active terminal when

the air flow decreases. The deficiencies of passive terminals, in connection with flowregulated installations, is one of the reasons why the VAV/DCV systems have not had a positive development. See fig-ures 12, 13 and 14.

Figure 12. The spread with active air terminals at a nominalair flow.

Figure 13. An active air terminal whose free air supply areadecreases to lower the air flow. The speed and strength of thespread remains unchanged. No risk of draught problems.

Figure 14. A passive air terminal whose free air supply area isconstant. If the flow is restricted, for example, with a damper,the air speed will diminish and the spread with turn down intothe occupied zone. Large risk for draughts.


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ACTIVE EXHAUST AIR TERMINAL DEVICEFlow control of the exhaust air
As the exhaust air terminal device does not have the sameproblem with varying air flow rates as the supply air terminaldevice, you can select simpler solutions. Criteria for an ex-haust air terminal device are:1. It ought to have the same regulation characteristics and

restriction range as the corresponding active supply air terminal device.

2. The appearance should match the supply air terminal device to give an attractive installation. Flow control of the exhaust air terminal device is handled by the same controller as the supply air terminal device. In the new series of controllers separate min/max settings can be programmed for supply and exhaust air terminal devices. This means that you can have different pressure control values for the supply/exhaust ducts.

TRANSFER AIR DEVICEOpen/Close door

In the selection of systems with transferred air and commonexhaust air in the corridor it applies that the transfer air deviceshould have a pressure drop <10 Pa at the maximum air flowand that trimming should be carried out with the door in theposition expected to be the dominating position. For example,office normally open doors, conference room and classroomsnormally closed doors. With an open door the air flow will in-crease to the same degree as if you have increased the pres-sure in the connecting duct with the pressure drop given bythe transfer air device. This condition is illustrated in figure 16,example: The maximum air flow at 80% opening and 40 Paconnection pressure gives a pressure drop across the supplyair terminal of 30 Pa equivalent to 50 l/s with a closed door.With an open door the pressure drop decreases by 10 Pa,which is utilized by the supply air terminal device whose flowthen increases 10 to 45 l/s. See figures 15 and 16.

Figure 15. Pressure condition in the transfer air system withopen or closed door.

Figure 16. Diagram that shows how the flow changes be-tween open/closed door.


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ROOMS WITH CLOSED DOORSRegulating supply/exhaust air flows in rooms with closeddoors is a recognized problem. This problem can manifest it-self as an imbalance that gives rise to large pressure differenc-es between rooms and corridors. To avoid this problem it isimportant that both the supply and exhaust controllers havethe same set value and that the flow ranges of the productsare respected.

Figur 17. Room with closed doors with active supply/exhaustair terminal devices. It is important that the constant pressuresensors are located in the room.

Figur 18. Room with closed doors with flow regulation forsupply/exhaust air. It is important that the exhaust air unit is“slaved” to the supply air unit’s set value


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ERIMIX SYSTEM
The erimix system is an optimising system for mixing hot/coldair in two duct systems with the aim of minimising the oper-ating costs and increase flexibility. The main principle is basedon a number of room controllers (max 9) which report roomstatuses to a mixing regulator which, based on room data, op-timises the mixing temperature of the supply air. The roomcontrol’s intelligence prevents the rooms from becoming coldif there is a heating requirement and at the same time the sup-ply air is colder than the room air and vice versa with a coolingrequirement. The system is completely integrated with othere.r.i.c. components and in doing so can handle both maintain-ing a constant pressure, slave flow control and active supply/exhaust air terminals. Control of the air flow to the room cantake place with more different control parameters such astemperature, CO2 and/or presence, for further informationsee the product sheet for the room controller KCD. In con-formity with other e.r.i.c. solutions, unit control with the Sys-tem Manager KSM can be used by the system to optimize fanoperations.Information about required zone temperatures can be collect-ed by the master system from the zone controllers and beused to optimize the temperature in the hot and the coldduct. The hot duct’s temperature can, for example, be con-trolled by the temperature requirement in the zone that de-mands the highest temperature and the cold duct by the zonethat requires the lowest temperature. In this way the capacityin both the ducts is utilized better at the same time as the en-ergy requirement is kept to a minimum.

Description of erimix system E1Fully developed system with active supply/exhaust air termi-nals and balanced air flow in each room. The room controllersRC3 adjust the air flow to the room and report a cooling orheating instance and terminal/damper positions to the zonecontroller SP1. SP1 handles maintaining a constant pressure inthe branch duct simultaneously with the mixing control ofhot/cold air in SPO. SP1 is equipped with temperature sensorsfor the duct temperature which is reported to respective roomcontrollers. Active exhaust air terminal devices are used in theexhaust air system as well as the maintaining of constant pres-sure with zone controller SP2.

Figure 19. Flow chart for erimix system E1.

List of components:SP0 Mixing box BLBSP1 Zone controller KZP with RC1 and temperatur unit

GT1GP1 Pressure sensor KSPTD1 Active supply air terminal device, for example, ACKGT3 Room unit KSTRC3 Room controller KCDSP2 Zone controller KZP with RC2 and temperatur unit

GT2FD1 Active exhaust air terminal device, for example,

AFK


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Description of erimix system E2System with full control of the supply air as in system E1, butwith transferred air to common controlled exhaust air flow.The exhaust air flow is controlled with zone controller SP2which obtains the set point value from the SP1 in the supplyair branch. This system also allows you to control the supplyair temperature against the common exhaust air temperature.


Description of erimix system E3System for constant air volume, or requirement control withother controllers than RC3. The mixing temperature on thesupply air is controlled by the common exhaust air tempera-ture. There is still constant pressure control with flow meter-ing on the supply air branch. There is a zone controller SP2 forslave control of the air flow and temperature metering on theexhaust air branch.


Description of erimix system E4System for variable air flow combined with mixing to give cor-rect supply air temperature. Slave control of the exhaust air ispossible using SP2 slave controller.Operation: If the room requires cooling, colder air is addedand the air flow is increased to spread the colder air in theroom. The reverse applies when heating is required.


List of components:SP0 Mixing box BLBSP1 Zone controller KZM with RC1 and temperatur

unit GT1GP1 Pressure sensor KSPTD1 Active supply air terminal device, for example, ACKGT3 Room unit KSTRC3 Room controller KCDSP2 Slave regulator KSA with RC2 and temperatur unit

GT2

List of comoponents:SP0 Mixing box BLBSP1 Zone controller KZM with RC1 and temperatur

unit GT1GP1 Pressure sensor KSPSP2 Slave controller KSA with RC2 and temperatur unit

GT2

List of comoponents:SP0 Mixing box BLBSP1 Zone controller KRF with RC1GT3 Room unit KSTSP2 Slave controller KSA with RC2


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PLANNINGUNITA few points to remember when selecting the unit:• The unit should be selected so that it can handle the entire
system’s working area. The working area is determined based on the sum of all minimum flows and an expected share of the sum of the maximum flows.

• With the use of System Manager (KSM) the unit control should be equipped with LON communication. Check that the input and output variables from the unit correspond with System Manager.

• The unit should be pressure controlled on both supply and exhaust air sides.

• As the flow varies in the system, the pressure drop across the filter also varies. Accordingly, it is not suitable to use a differential pressure gauge for indication of filter replace-ment. It is recommended instead that the filter is replaced, for example, once a year (depending on the load and requirement).

• The temperature control of the supply air can have a deci-sive effect on the fan and cooling machine’s energy usage. The temperature control should be selected based on the geographical position and expected thermal loads. If direct expanding cooling (DX cooling) is used, checks should be made that the cooling (compressors) also work at the sys-tem’s minimum flow. The supply air temperature should also be compensated for the outdoor temperature.

• The fresh air intake ought not to be placed on the south face, close to felt roofs or other heat sources (resulting in unnecessary energy consumption in the summer).

• Placement of the unit’s pressure sensor. The pressure sen-sor for the supply air should be suitably placed by the last sub branch in the main duct and the exhaust air pressure sensor by the branch that requires the most negative pres-sure. If a System Manager is used it is unimportant, from an energy point-of-view, where in the main duct the sen-sors are placed, yet in order to reduce cable routing the recommended placement is close to the unit.

• Check the risk of the anti-freeze protection tripping at low outdoor temperatures and minimum flow.

SYSTEM MANAGER (KSM)System Manager is a LON based controller that communicateswith the unit and all branch dampers (KZP, KZM, KRF andKSA). Respective damper angles (0–100%) are sent from theduct dampers to the System Manager which selects thedamper that is open the most. If the most open damper is fullyopen the System Manager sends a new pressure set point val-ue that is higher than the current actual value to the fan. Thefan now increases speed to the new set point value and themost open damper closes slightly and the pressure on thisbranch can be guaranteed. If the flows in the system decrease(pressure drop decreases),for example, at lunch, the damperthat is open the most will be less open than in the previous in-stance.The System Manager now does the reverse of the previous in-stance, and sends a lower pressure set point value to the fanuntil the damper that is open the most is nearly fully open(90%). It is possible to connect 50 dampers to the SystemManager, of which 35 are supply air and 15 exhaust air damp-ers. Special variants can occur.The advantages of a System Manager (KSM) is that you re-duce the system’s noise generation both in the fan and duct

system and furthermore reduce energy consumption at lowerflows than the maximum flow. The System Manager also fa-cilitates trimming and commissioning as the pressure set pointvalues to the fan do not need to be “found”.It is very important that the different zones in the duct systemare dimensioned the same (same pressure drop). If one zonerequires a higher pressure this will then dominate over theunit pressure.

MAIN DUCTSThe main ducts are primarily selected from a noise point-of-view, normally a maximum of about 7 m/s. If the system is notexpected to supply maximum flow to all rooms at the sametime, a simultaneity factor (70–90 %) is usually presumed andsystem is selected for the simultaneity factor multiplied by themaximum flow. Smaller main ducts naturally increase energyconsumption as this will require the fan to work up a higherstatic pressure. If a System Manager is used this high pressurewill only be a set point value for the fan when the load on thesystem is high.


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BRANCH DUCTS/SUB BRANCHESThe branch ducts are selected based on the maximum flow onthe branch and 5 m/s. This diameter is kept constant over theentire branch. Higher velocities can be permitted under thecondition that noise generation at maximum flow is observed.Ideally a silencer is positioned after the damper (KZP or KZM)which handles maintaining a constant pressure. Branches areselected for 3 m/s at maximum flow or a maximum pressuredrop of 10% of the constant pressure in the branch duct.

SUPPLY AIRIn the e.r.i.c. system a pressure sensor is placed in the branchduct (see figure). The placement of the pressure sensorsshould be such that the pressure drop to all terminals with var-iable flow is the same at full flow (general rule: centre of thebranch).

Why should the diameter of the branch be constant?If the pressure sensor is positioned in the centre of the branchand the pressure is kept constant, the pressure at the begin-

ning of the branch will be higher than the pressure at thepressure sensor.If the diameter is constant, the speed will be at it highest atthe start of the branch and a high speed means that the pres-sure drop in the sub-branch is greater for the coming sub-branches where the speed is lower.

What happens if the pressure drop is not the same?Active terminals are used to maintain a constant outlet veloc-ity, which eliminates the risk of draught throughout terminal’sflow interval. When active terminals are used, in some cases(not rear edge) a restrictor is placed in the outlet of the termi-nal. If there are then large variations in the pressure drop fromthe branch to the terminal this will require a higher pressurethan is ideal for a terminal with has a favourable placement,this means that it must be throttled. When throttling is doneat the outlet this will affect the throw lengths and even noisegeneration will be higher. If a damper that works with posi-tions is used instead of an active terminal the differences inpressure only come into play in the noise generation from thedamper. It is appropriate to make a pressure drop calculation.

Figure 23. Example of full flow.

The dynamic pressure is approx. 5 Pa in the duct from the sub branch to the terminal. The following conditions prevail in points 1 to 4.1. 5 m/s and approx. 45 Pa static pressure and 15 Pa dynamic pressure2. “High” velocity gives a large pressure drop, approx. 7 Pa. The pressure drop after the branch is a further 3 Pa.3. Here the static pressure is constant 40 Pa.4. The velocities are now halved and the pressure drop in the branch is only approx. 2 Pa.


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Why are low velocities (<3 m/s) preferable between the branch and terminal?The reason for this is to ensure low sound data in the entireflow interval and to maintain high control authority over theterminal. Presuppose that we need 40 Pa in the terminal toobtain full flow with the terminal fully open. If the pressuredrop is now large (high speed or large distance) between thebranch and the pressure sensor, for example, 15 Pa, this willrequire a pressure of 55 Pa in the branch. When the system/
room then switch to minimum flow, the velocities drop andwith sufficiently low minimum flow the pressure drop will bevirtually zero from the branch to the terminal. This means thatwe must take 40 + 15 = 55 Pa across the terminal, which giveshigher noise generation and the sound data for 55 Pa and theminimum flow must be checked. The advantage is that we re-ceive a greater throw length, which gives an even smaller riskfor draught problems at minimum flow.

Figure 24. Minimum flow.

The same branch duct but with a minimum flow of 20%. The velocities are now so low that the duct system in principle operates as a pressure box. The following conditions prevail in points 1 and 2.1. 1 m/s and approx. 41 Pa.2. Here the pressure constant is 40 Pa.


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Figure 25. Duct selection according to the e.r.i.c. system with constant duct diameter.

1. Traditional system2. e.r.i.c. system


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Figure 26. Aim for symmetry.

1. Traditional system.2. e.r.ic. system.3. Okay, bhut higher pressure at minimum flow.


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Figure 27. Aim for equal pressure drop from the branch duct to the terminal by increasing the duct diameter to the most poorlyplaced terminal.

1. Traditional system.2. Better, larger duct to most distant terminal.


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EXHAUST AIRIn the exhaust air system the pressure sensor is placed in thefurthest part of the branch to give an equivalent pressure dropacross all exhaust air terminals in the branch. General rule: Inthe furthest part of the branch.
The same selection rules apply to the exhaust air branches asfor the supply air. Some basic points to consider:• Constant duct diameter• Regular branch solutions

Figure 28. Placement of the pressure sensor in an exhaust airbranch.

1. Here the static pressure is 27 Pa.2. Here the pressure is constant.

Possibility to ensure low flowsTo ensure a flow in a duct often requires a measurement pres-sure of at least 3 Pa. 3 Pa corresponds to a speed of 1.5 m/s(varies depending on the measurement technique) which inmany cases is over 20% of the maximum flow. In the e.r.i.c.system there are active terminals which have been measuredin the laboratory. A pressure in the distribution box is meas-ured and the flow is determined by the opening.Accordingly, in principle it is possible to measure the flowdown to 10% of the maximum flow with good accuracy andwith a fully closed terminal you only obtain the leakage flowat the pressure in question.• Low noise levels

By maintaining the pressure constant at a branch, level noise levels drop with a reduced flow.

• Reduced material costsOnly one pressure sensor per branch is required and no pressure sensor for the room with variable flow. You can combine traditional terminals with constant flow and active terminals and variable flow. Here VAV control is required in a traditional VAV system to maintain a constant flow.

No control equipment is installed in the rooms with constantflows only a traditional terminal, this is because the pressurein the branch duct is constant. The terminal is selected to givethe selected flow with the damper as open as possible and theavailable pressure in the branch duct.


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TERMINALSAt a constant pressure the flow is determined based on theopen area. If the pressure is constant and we know the openposition of the terminal or damper, we also know the flow.

Why should you work with positions and presure in-stead of the traditional flow metering (VAV)?There are several reasons for this:• More stable systems

If the pressure should temporarily increase, the terminals would not be able to close to maintain the flow (no meas-uring is performed here at the terminal) but they would remain in the same position, which reduces the risk of fluc-tuations in the system.

• Longer life span/reduced maintenance costsAs the terminals remain in the same position, even if the pressure should temporarily change, the number of cycles on the terminal also drops and in doing so extends the life span. The pressure sensor, which is on the branch, is a static pressure sensor (diaphragm), this means no air passes the sensor and thereby it does not need to be cleaned.

Figure 29. When subdividing the branch duct in each direc-tion two pressure reguator units should be used.

BALANCINGIn principle there are two ways to balance the supply and ex-haust air in the e.r.i.c. system.Balanced supply and exhaust air in all roomsIn this case balancing is performed in the room. Both the sup-ply and exhaust air branch are pressure controlled. A control-ler (KCD) controls the supply air terminal device (or thedamper) between a maximum position and minimum positionthat corresponds to the flows. The exhaust air terminal device(or the damper) is controlled by the same controller and ad-justs even this between two positions. If you want a negativepressure in the room, you increase the maximum and mini-mum positions for the exhaust air. It is okay to connect termi-

nals with constant flows on both the supply and exhaust airbranches. Advantage: Possibility to reduce to low minimumflows with good accuracy. Disadvantage: More expensive in-stallation on the exhaust air side than in figure 31.

Figure 30. Balanced supply and exhaust air in all romms.

Supply air in the rooms and central exhaust air (trans-ferred air)In this case the supply air branch is pressure controlled and thesupply air flow rate in the branch is measured (KZM) to thenbe sent as the set point value to (KSAa) the exhaust air branch.The supply air is controlled as required in the different roomsand exhaust air is taken in other areas. If you want a negativepressure, the set point value can be displaced either in a fixedflow (l/s) or as a percentage of displacement on the measuredsupply air flow.The terminal cannot be connected with con-stant flows on the exhaust air side. Preferably separate ex-haust air ducts for toilet groups and wet rooms are routed toeither the main exhaust air duct or to a separate fan.The zone’s (the branch’s) exhaust air is ideally taken from ar-eas such as the corridor or copying room. If you design to havemore supply air branches than exhaust air branches, it is pos-sible to send these supply air flows to an exhaust air branch(KSA), which adds these supply air flows to an exhaust sideflow (maximum 5 from product revision KSAb). Advantage:Simpler and less expensive installation on the exhaust air sys-tem. Disadvantage: During designing it is important to checkwhether the selected branch dampers can handle minimumflows (due to flow metering instead of pressure control). Sep-arate ducts to the exhaust air terminal device with constantflows. See figure 31.

Figure 31. Supply air in the rooms and central exhaust air(transferred air).

INSULATIONAs chilled air is transported in the air duct system the supplyair ducts should be insulated from the risk of condensationand heating of the supply air. Please refer to the insulation


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manufacturer’s calculation software. In order to reduce theabsorption of heat it may be necessary to reduce the duct sizeat the end of the branch duct. This is done when the velocityfalls below 1.5 m/s.

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PLANNING – ELECTRICAL AND CONTROL INSTALLATIONINTRODUCTIONThe e.r.i.c. system requires a professional electrical and con-trol installation for reliable operation.Installation can be broken down into three groups:• Power supply• Control signals• Data communication All documentation for the e.r.i.c. system can be downloadedas files from our website.

SYSTEM OVERVIEW1. Power supplyIt is important that transformers are rated so that the voltagestays within the range 24 V AC ± 10%. The transformer fuserating must not exceed 6 A to prevent the circuit board fromburning out in the event of a short-circuit else-where in thesystem. The recommended cable cross-section between trans-former and controllers is 1.5 mm2. For smaller transformersthe cable cross-section can be reduced, but the voltage toler-ance must never be exceeded. To simplify calculation of thetransformer rating a program (ericTrafoDim.xls) can be down-loaded from our website on the internet. Search under soft-ware.2. Control signalsIn this case we refer to cables that are not required to supplypower to controllers or active devices. Cables can be simple indesign and have a smaller cross-section. This applies to cablesbetween room controllers and room accessories such as KST,KSO and KSC. The recommended cable is EKKX 0.5 mm forcable lengths under 10 m. Use EKKR 1.0 mm for cable lengthsof 10–30 m. For active devices such as ACK, AFK and AKY themaximum cable length is 50 m. For longer cable lengths con-tact Swegon for advice.3. Data communicationAll data communication between controllers is by LonTalk us-ing the LonWorks protocol. There are three levels for commu-nication with the e.r.i.c. system:• Stand-alone with master/slave connections• Stand-alone with link to system manager• Property network linked to master system All connections between products must be made using datacable approved by the LonMark organization. We always rec-ommend the use of Belden cable type 8471. Networks mustbe designed according to the relevant guidelines to ensure re-liable communication. See the Echelon website at www.ech-elon.com.

TOOLSA computer program and wiring diagrams can be download-ed from our website on the Internet. This allows a detailed di-agram to be created showing only the relevant components.Transformer requirements can be determined using an MS Ex-cel spreadsheet that can be downloaded from our website.


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ROOM REGULATION USING KCD AND ACTIVE AIR TERMINAL DEVICES
Figure 32.

Cable typesPower is supplied to KCD using two-core cable with a mini-mum cross-section of 0.75 mm2.Signal and power cable to active devices must be three-corecable with a minimum cross-section of 0.75 mm2. Suitable ca-ble is EKKR 3 x 1.0 mm with a maximum 50 m cable lengthfrom KCD to the most distant device (connection points A–F).The maximum length of 50 m can only be used if all connec-tions and junctions are made without a voltage drop. If thereare more than four air terminal devices they must be dividedinto two groups, with each group connected by its own cabledirect to the controller.Other signal cables may be EKKX 0.5 mm for cable lengths un-der 10 m, above which we recommend EKKR 1.0 mm up to30 m.LON connections (dotted in diagram) must be made usingBelden type 8471 cable.

Room controller KCDThe room controller KCD (detail A) is available in enclosed ornon-enclosed versions.Up to eight active air terminal devices can be connected to thesame output on the controller. The devices must be dividedinto groups with separate cables connected direct to the con-troller, and a maximum of four active devices in each group.This does not apply to ARP or ARE, which can be connectedto a maximum of 10 devices without splitting into groups.

Figure 33. Detail A.


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KST room unitSeveral variants of the room unit KST (detail B) are availablefor setting the desired room temperature, and these have dif-ferent signal cable requirements. KST 4 is connected usingseven-core signal cable and two-core LON cable. KST 2 is con-nected using six-core signal cable and two-core LON cable.KST 0, which only provides temperature measurement, justrequires two-core cable.

Figure 34. Detail B.

Motion detector KSOMotion detector KSO (detail C) for detecting human pres-ence. Not suitable for alarm functions.Connected using 3 x 1,0 mm signal cable.

Figur 35. Detalil C.

Radiator actuatorsTwo types of radiator valve actuators (detail E) can be con-nected to the regulator KCD. Different types cannot be usedwith the same regulator.Radiator valve actuator for 24 AC with 0–10 V DC control.Connected using 3 x 1.0 mm signal cable. A maximum of 10units can be connected to the same output (Y1).Radiator valve actuator for 24 AC ON/OFF control. Connectedusing 2 x 1.0 mm signal cable. Connected to output (V1) max-imum 0.8 A (20 VA) load. This valve type usually has a higherpower consumption; typically no more than four can be con-nected to each controller.

Figure 36. Detail E.

Carbon dioxide sensor KSCCarbon dioxide sensor KSC (detail D) for monitoring air qual-ity. Connected using 3 x 1.0 mm signal cable. Three variantsof KSC are available. KSC 0 is connected differently thanshown here.

Figure 37. Detail D.

Junction boxJunction box (detail F) for branching to several air terminal de-vices. Use this for all types of cable branches, including LONcable. This is not supplied by Swegon.

Figure 38. Detail F.

Wiring diagrams are given in the respective productdata sheets.


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ROOM CONTROL USING KCW AND CEILING DAMPERS.
Figure 39.

Cable typesPower is supplied to KCW using two-core cable with a mini-mum cross-section of 0.75 mm2.Signal and power cable to active devices must be three-corecable with a minimum cross-section of 0.75 mm2. Suitable ca-ble is EKKR 3 x 1.0 mm with a maximum 50 m cable lengthfrom KCD to the most distant device (connection points A–J).The maximum length of 50 m can only be used if all connec-tions and junctions are made without a voltage drop. If thereare more than four air terminal devices or damper motors theymust be divided into two groups, with each group connectedby its own cable direct to the controller.Other signal cables may be EKKX 0.5 mm for cable lengths un-der 10 m, above which we recommend EKKR 1.0 mm up to30 m.LON connections (dotted in diagram) must be made usingBelden type 8471 cable.

Room controller KCWThe room controller KCW (detail A) is available in enclosed ornon-enclosed versions.Up to eight active air terminal devices can be connected to thesame output on the controller. The devices must be dividedinto groups with separate cables connected direct to the con-troller, and a maximum of four active devices in each group.This does not apply to ARP or ARE, which can be connectedto a maximum of 10 devices without splitting into groups.

figure 40. Detail A.


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Figure 42. Detail C.

Radiator actuatorsTwo types of valve actuators (detail E) can be connected tothe regulator KCD to control chilled beams or radiators. Dif-ferent types cannot be used with the same controller.Valve actuator for 24 AC to increase/decrease flow. Connect-ed using 3 x 1.0 mm signal cable. Outputs V1–V4 and G0 onthe controller KCW can have a maximum load of 0.8 A. Werecommend that no more than 10 units are connected to thesame output.Valve actuator for 24 AC ON/OFF control. Connected using 2x 1.0 mm signal cable. Connected to output (V1 or V3) maxi-mum 0.8 A (20 VA) load. This valve type usually has a higherpower consumption; typically no more than four can be con-nected to each controller. See wiring diagram.


Carbon dioxide sensor KSCCarbon dioxide sensor KSC (detail D) for monitoring air qual-ity. Connected using 3 x 1.0 mm2 signal cable. Three variantsof KSC are available. KSC 0 is connected differently thanshown here.


Damper unit AREDamper unit for air flow control (detail J), 24 AC with 0–10 VDC control. Connected using 3 x 1.0 mm signal cable. A max-imum of 10 units can be connected to the same output (Y1).

Figure 45. Detail J.



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ROOM CONTROL USING KRF AND AIR TERMINAL DEVICES
Figure 46.

Cable typesPower is supplied to KRF using two-core cable with a mini-mum cross-section of 0.75 mm2. Signal cables can be EKKX0.5 mm for cable lengths under 10 m, above which we rec-ommend EKKR 1.0 mm up to 30 m.LON connections (dotted in diagram) must be made usingBelden type 8471 cable.KRF can also slave-control a corresponding exhaust air con-troller, in which case it must be linked to it. The link may useanalogue or digital communication of air flow. The choiceshould be made before KRF is manufactured. The suppliedconfiguration document specifies which system has been cho-sen.

Detail A KRFHere the room regulator is mounted on the duct section thathandles air flow control. The cables connected to the control-ler have the number of cores shown in the diagram.

Figure 47. Detail A.


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Figure 49. Detail C.

Radiator actuatorsTwo types of radiator valve actuators (detail E) can be con-nected to the controller KCD. Different types cannot be usedwith the same controller.Radiator valve actuator for 24 AC with 0–10 V DC control.Connected using 3 x 1.0 mm signal cable. A maximum of 10units can be connected to the same output (Y1).Radiator valve actuator for 24 AC ON/OFF control. Connectedusing 2 x 1.0 mm signal cable. Connected to output (V1) max-imum 0.8 A (20 VA) load. This valve type usually has a higherpower consumption; typically no more than four can be con-nected to each controller.


Carbon dioxide sensor KSCCarbon dioxide sensor KSC (detail D) for monitoring air qual-ity. Connected using 3 x 1.0 mm signal cable. Three variantsof KSC are available. KSC 0 is connected differently thanshown here.






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CONSTANT PRESSURE CONTROL OF SUPPLY AND EXHAUST DUCTS WITH KZP AND KSP
Figure 53.

Cable typesPower is supplied to KZP using two-core cable witha minimum cross-section of 0.75 mm.For signal cables we recommend EKKR 1.0 mm up to 30 m.

Damper unit KZPPressure-controlling damper unit (detail K). Power supply ca-ble, pressure sensor cable and LON cable (if required) are con-nected to the controller (KZP). The damper units are oftenmounted using a quick-fit connection FSR (detail J).

Figure 54. Detail K.

Pressure sensor KSPThe pressure sensor KSP (detail G) is mounted on the duct sys-tem and is connected using 3 x 1.0 mm signal cable.

Figure 55. Detail G.




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CONSTANT PRESSURE CONTROL OF SUPPLY DUCT WITH KZM, AND SLAVE FLOW CONTROL OF EXHAUST DUCT WITH KSA

Figure 57.

Cable typesPower is supplied to KZM and KSA using two-core cable witha minimum cross-section of 0.75 mm2.For signal cables we recommend EKKR 1.0 mm up to 50 m.LON connections (dotted in diagram) must be made usingBelden type 8471 cable.KZM can also slave-control a corresponding exhaust air con-troller KSA, in which case it must be linked to it. The link mayuse analogue or digital communication of air flow. The sup-plied configuration document specifies which system hasbeen chosen. LON cable is used for digital communication,while signal cable is used for analogue communication be-tween the units.

Damper units KZM and KSAPressure-controlling damper unit KZM and flow-controllingdamper unit KSA (detail K). Power supply cable, pressure sen-sor cable and LON cable (if required) are connected to thecontroller.A cable for slave flow communication is connected betweenKZM and KSA. The damper units are often mounted using aquick-fit connection FSR (detail J).

Figure 58. Detail H.

Pressure sensor KSPThe pressure sensor KSP (detail G) is mounted on the duct sys-tem and is connected using 3 x 1.0 mm signal cable.

Figure 59. Detail G.





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BINDINGS FOR DATA COMMUNICATIONSINTRODUCTIONThese instructions simply explain which variables are normallybound to enable the e.r.i.c. system to work in its most basicform. In addition to the information given here there is verydetailed documentation on the various controller data varia-bles in Swegon’s Handbook, which is now in its "Third edi-tion" and can be downloaded from our website on theInternet.To create bindings as described the user will require a copy ofLonMaker for Windows and a working knowledge of the soft-ware. Other tools can also be used to establish data commu-nication between network nodes, but the variable names willbe the same, since these are tied to the LonTalk system. Whensetting up devices it is recommended that you use XIF files forthe applicable controller type. These can be downloaded fromour website on the Internet. When commissioning controllersit is important to select the function “current values in de-vice”, as all controllers are factory configured for their task.Controllers are supplied with a configuration document,which can also be ordered from the sales office that suppliedthe product. Configuration documents are only available aspdf files.Unfortunately we cannot supply plugins at present.
Binding levelsWith the e.r.i.c. system you can choose to use network cablesolely between the master and slave units. These bindings be-tween two units (one master + one slave) or six units (fivemasters + one slave) can be set at the factory before delivery.If this is the case it is important that only those units that arebound to each other are connected to each other by local net-work cable. They must not be connected to other units by net-work cable.In systems with a complete network loop between all e.r.i.c.controllers, the bindings must be established by a contractoron site. To make this task easier Swegon can supply configu-ration forms that have bar code labels bearing the Neuron IDnumber. Contact your nearest sales office for information onordering e.r.i.c. controllers with NID labels.

Technical data for controllersGenerally, all KC_ controllers are LonMark approved accord-ing to LonMark_Guidelines 3.2 and the profiles given in thetable.

Technical data for LonMaker for Windows

Controller variantsFour different controllers are used with the e.r.i.c. system, andcontrollers are always referred to by their two initial letters,KC_. Two models of controller are used in duct products, ofwhich there are four different variants. When a product is in-stalled in LonMaker it is the controller designation that is seen,not the product description. The following list gives the prod-uct names against the controller names.

LonTalk channel type TP/FT-10, 78 kbsNeuron type 3150, 10 MhzController KCP Functional profile 8010Controller KCF Functional profile 8010Controller KCD Functional profile 8010Controller KCW Functional profile 8070

LonMaker requirements ver. 3.00 or later

Zone controller KZP KCPZone controller KZM KCPSlave controller KSA KCPRoom controller KRF KCFRoom controller KCD KCDRoom controller KCW KCWSystem manager KSM KSMControllers have undergone continuous updating, and this is reflected in the generation letter after the product name. Current variants are KCPb, KCFc, KCDb, KCWa and KSMb. IXF files for all variants and generations can be downloaded from our website on the Internet.


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1. SLAVE CONTROL OF SUPPLY AND EXHAUST AIRSlave control requires that the master KZM or KRF is bound tothe slave unit KSA. Up to five master flows can be bound to aslave unit, which adds up all the partial air flows.

Any change in the slave state is made from the master by set-ting nviOfsSlaveState to LOW for a percentage shift, or toHIGH for a fixed change in l/s. The size of the change in theset value is specified in the master using nviOfsSlavePerc (–100%–+100%) to give the percentage change, or nviOf-sSlaveFlow (–1,000–+1,000 l/s) to give the change in l/s.Note: A controller that is used in KZP, KZM and KSA has thedesignation KCP. KRF’s controller has the designation KCF.

Figure 61. Binding between master and slave. The diagram shows the binding of three masters to one slave unit.

From Master To Slave UnitnvoSetpFlowSlave nviSetpFlowSlave


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2. SYSTEM MANAGER KSMFrom the branch controllers KZM, KZP, KSA, andKRF if this is a separate branch, the damperpositions must be bound to the system managerusing the variable type SNVT_lev_percent as follows:
Supply air

The first branch controller is bound to nviDampPos1Su; thesecond to nviDampPos2Su and so on.The controllers must be bound from Pos1 upwards; no posi-tions can be skipped. A maximum of 35 supply air damperscan be bound to System Manager KSMb. The earlier KSMawas limited to 10 dampers. Special variants may occur.

Exhaust air

The first branch controller is bound to nviDampPos1Ex; thesecond to nviDampPos2Ex and so on.The controllers must be bound from Pos1 upwards; no posi-tions can be skipped. A maximum of 15 exhaust air damperscan be bound to System Manager KSMb. The earlier KSMawas limited to 10 dampers. Special variants may occur.

Figure 62. Bindings between zone dampers and System Manager. Master-slave bindings between zone dampers are not shown inthis diagram. Note the difference between KZP/KZM and KRF/KSA. The variable nvoDampFlowVal must be bound for KRF/KSA.

From KZM and KZP To System ManagernvoDampPressVal nviDampPos1SuFrom KRF and KSA To System ManagernvoDampFlowVal nviDampPos1SU

From KZP To System ManagernvoDampPressVal nviDampPos1ExFrom KSA To System ManagernvoDampFlowVal nviDampPos1Ex


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Air handling unitSystem Manager requires that the unit’s supply/exhaust fansare equipped with pressure control equipment that is capableof LonTalk communication. All variables for pressure, start-upchecks and damper positions must be bound. It is possible toexclude a complete system and just control the supply air side,for example.The actual values and set values for the supply/exhaust pres-sures after the unit are bound to the System Manager usingthe variable type SNVT_lev_cont (0–100%) orSNVT_press_f (0–xx Pa). It is possible to bind a System Man-ager to each supply fan and each exhaust fan.

Actual values for supply air and exhaust air

The variable name in the unit’s LON module can vary, but the type must remain the same.

Set values for supply air and exhaust air

The variable name in the unit’s LON module can vary, but the type must remain the same.

Start-up checkThe System Manager will only control the pressure when theunit is in operation, so it is necessary to have the followingbinding with variable type SNVT_state or SNVT_switch fromthe unit:

Actual values for supply air and exhaust air

If this binding is omitted, KSM will not provide control.For the variable nviStartControl (SNVT_state, consists of 16bits) from the unit drive, bit(0) is used for information transfer.Value 0 = unit switched off, 1 = unit in operation.For the variable nviStartCntrlSw (SNVT_switch), value 0 =unit switched off, 1 = unit in operation.Notes (1 and 2) Only one of the variables should be bound.

Figure 63. Bindings between System Manager and GOLDunit, earlier model.

Figure 64. Bindings between System Manager and GOLDunit, series C model, equipped with LON module.

From Gold C unit To System ManagernvoSF_pressure nviPressSupplyPr(1)

(nviPressSupply(1))

nvoEF_pressure nviPressExhustPr(2)

(nviPressExhaust(2))

From System Manager To Gold C unitnvoSpPressSuPr(1)

(nvoSpPressSu(1))nviSF_HSpressure

nvoSpPressExPr(2)

(nvoSpPressEx(2)) nviEF_HSpressure

From Gold C unit To System ManagernvoUnitOPM2_12 nviStartControlSw(1)

(nviStartControl(1))


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3. ROOM CONTROLLERS KCD, KCW AND KRFThe e.r.i.c. system does not require binding with the roomcontrollers, but binding is required with erimix systems E1-E3.Data that can be obtained from the room controllers includesactual temperature, set temperature, heating or cooling de-mand (–100%–+100%), CO2 level and damper opening (0–100%). More information about the various input and outputvariables for the room controllers can be found in the productdata sheets and the controller handbook.
4. ERIMIX SYSTEM E1-E3The system is based on communication between the roomcontrollers KCD and mixing controller – usually KZM (may alsobe KZP). The controllers KCD report whether there is a heatingdemand or cooling demand and the level of this demand us-ing the variable nvoDampPos (SNVT_Switch). KZM reportsthe mixed supply air temperature back to the room controllerKCD so that this does not try to provide cooling when the sup-ply air temperature is too high, and vice versa. In an erimix sys-tem with slave-controlled exhaust air the slave air flow mustbe bound between KZM and KSA. See figure 65.

Figure 65. Bindings between room controllers KCD and mixing controller KZM with slave controller KSA. A maximum of nine roomcontrollers can be bound to one KZM (KZP).


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Techn

ical section

COMMISSIONINGBelow follows a brief description of the trimming procedure:

The traditional trimming of terminals and dampers, which isusually time-consuming and expensive, does not need to bedone on the e.r.i.c. system. Swegon programs respective sys-tem controllers before delivery for a specific static pressure inthe different branch ducts using its own configuration tools.Therefore it is essential that the controllers are installed in theright place in the system. A labelling system is used for the in-stallation work. The only action needed to be taken on site isto check, via the operator panel, that the set values are cor-rect. You can read more about trimming and inspection in theTrimming Manual for the e.r.i.c. system, which can be down-loaded from our website.


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APPLICATIONS
Office

Figure 66. Office with balanced supply and exhaust air in each room. Separate constant pressure control in the supply and exhaustair branches

1. Acitve supply air terminal device2. Transfer air device3. Active exhaust air terminal device4. Exhaust air terminal5. Radiator valve6. Window contact


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Techn

ical section

Office

Figure 67. Office with supply air in each room. Transferred air to corridors and central exhaust air. Supply and exhaust air flowsare balanced through slave control of the exhaust air.

1. Active supply air terminal device2. Transfer air device3. Common exhaust air4. Exhaust air terminal5. Radiator valve6. Window contact


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Office
Figure 68. Office with supply air in each room. Cellular office with active chilled beams. Supply and exhaust air flows are balancedin the room. Separate constant pressure control in the supply and exhaust air branches.

1. Active supply air terminal device2. Transfer air device3. Active exhaust air terminal device4. Exhaust air terminal5. Radiator valve6. Window contact7. Cooling valve8. Ceiling unit


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Techn

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Lecture theatres

Figure 69. Classrooms with balanced supply and exhaust air. Separate constant pressure control in the supply and exhaust airbranches.

1. Active supply air terminal device2. Transfer air device3. Active exhaust air terminal device4. Exhaust air terminal


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Hotels/Healthcare facilities
Figure 70. Hotels/Healthcare facilities with balanced supply and exhaust air in each room. Separate constant pressure control inthe supply and exhaust air branches.

1. Active supply air terminal device2. -3. Active exhaust air terminal device4. Exhaust air terminal5. Radiator valve


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e.r.i.c. technical section 2006 archive/flow control... · 2009. 8. 31. · technical section-----...

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