6. Tool box. Theory. Heating. Life Cycle Cost. Speed Control FLOW THINKING. Basic pump theory Mixing loops. Basic theory. Calculation Example

Transcription

1 FLOW TINKING 6. Tool box Theory Basic pump theory Mixing loops eating Basic theory Life Cycle Cost Calculation Example Speed Control Control mode Control mode Constant curve Constnat diff. pressuer Proportional pressure (calculated) Proportional pressure (measured) Temperature control Constant Flow Constant pressure

2 FLOW TINKING Theory BASIS PUMP TEORY X CURVE The pump performance curve is shown in the diagram, where (flow) is the X axis and (head) or p (pressure) is the Y axis. = m 3 /; l/s; m 3 /s = mwc; p = kpa p - EFFECT CURVE The effect curve is showing P (effect) at the Y axis and at the X axis. P = x p η or P = ρ x g x x η η = efficiency; ρ = density; g = acceleration due to gravity The P curve can be P1 or P2 depending on the pump type. P = W; kw; P P P NPS CURVE NPS (Net Positive Suction ead) is an expression for the pressure lost in the pump, and together with the vapour pressure, it is used to calculate the inlet pressure needed at the pump to avoid cavitation. The NPS curve is showing (head) at the Y axis and at the X axis. NPS 162

3 Theory BASIS PUMP TEORY EFFICIENCY CURVE The curve is showing the η (efficiency) of the pump. The efficiency is measured in %. All pumps have a best point (η max. ), showing where the pump has the highest efficiency. The efficiency of the pump depends on the pump size and the quality of the construction/production. Small pumps have a lower efficiency than large pumps. η η max. INDUCED EFFECT P1 is the total induced effect to the pump system. P2 is the effect coming from the motor (shaft effect). The difference between P1 and P2 indicates either the efficiency of the motor (η mot. ), or the efficiency of the motor (η mot. ) + the efficiency speed regulation (η reg. ). P3 is the effect induced to the pump. P4 is the hydraulic effect ( x ). The difference between P3 and P4 indicates the efficiency of the pump (η pu ). P 1 P 2 P 3 P 4 η reg. η mot. η pu. DUTY POINT The duty point is at the intersection between the curve and the system characteristics. Duty point 163

4 FLOW TINKING Theory BASIS PUMP TEORY SYSTEM CARACTERISTICS The system characteristics show the pressure lost in the system as a function of the flow. The starting point of the characteristics depends on the type of system. a a. In a closed system (circulation of liquid) it will always start at 0.0 (0 flow; 0 head). b. In an open system (transport of liquid) the starting point depends on geo (geometric lift). b geo SYSTEM CARACTERISTICS System characteristics in parallel will decrease. orizontal addition. C 1 C 2 C 1 + C 2 C 1 C 2 SYSTEM CARACTERISTICS System characteristics in series will increase. Vertical addition. C 1 C 1 C 2 C 2 C 1 + C 2 164

5 Theory BASIS PUMP TEORY SYSTEM CARACTERISTICS Common for all system characteristics is that there is a connection between (flow) and (head). If is decreased to ½, will be decreased to ¼. PUMPS IN PARALLEL Pump in parallel will increase. orizontal addition. For 2 identical pumps the maximum will double. Maximum will be the same. Normally used in pump systems. Pu 1 Pu 2 Pu 1 +Pu 2 Pu 1 Pu 2 PUMPS IN SERIES Pumps in series will increase. Vertical addition. For 2 identical pumps the maximum will double. Maximum will remain the same. Normally used in multi-stage pumps. Pu 1 Pu 2 Pu 1 Pu 2 Pu 1 + Pu 2 165

6 FLOW TINKING Theory BASIS PUMP TEORY DRIVING PUMP CURVE The driving pump curve shows the total effect of the positive pump curve and the negative system characteristics (Pu C = X). This is used to give a graphic picture of a hydraulic connection of systems. X curve C Pu X Pu C X REVOLUTION OF TE PUMP By changing the revolutions of the pump (n) to a lower or higher speed, the pump curve will also change. n = 1.25 n = 1.0 n = 0.75 n = 0.5 n =0.25 CONNECTED POINT Affinity equation: n 1 1 / 2 = n 1 /n 2 1 / 2 = (n 1 /n 2 ) 2 P 1 /P 2 = (n 1 /n 2 ) n 2 P 2 1 P 1 P 2 166

7 Theory BASIS PUMP TEORY Boiler: Φ = 210 [kw] t = 20 C = 9.1 [m 3 /h] = 1.5 [m] Constant temperature Variable flow Pu2 Radiator system: Φ = 160 [kw] t = 20 C = 6.9 [m 3 /h] = 3.5 [m] Variable temperature Constant flow ot water production: Φ = 50 [kw] t = 20 C = 2.2 [m 3 /h] = 2.0 [m] Constant temperature Variable flow M C2 Pu1 M C3 C1 4.0 Calculated duty point m Pu1 UPS PuX 1 C Pu2 UPS 40-60/2 F Calculated duty point PuX 2 PuX 1+2 C 2 C m 3 / m 3 / YDRAULIC CONNECTIONS Example of using the graphic method and driving pump curves to determine the right selection of more that one pump in a system. In this case two pumps share the pressure lost in part of the system (the boiler). The diagram shows the maximum head of both pumps needed to secure the right maximum flow. The head in the radiator system has to be adjusted to limit the flow PUMP DATA: Pu1 = UPS = 4.0 [m] = 2.2 [m 3 /h] Pu2 = UPS 40-60/2F = 5.2 [m] = 7.6 [m 3 /h] (without adjustment) 167

8 FLOW TINKING Theory MIXING LOOPS Mixing loops and control valves System 1 System 2 System 3 System 4 System 5 System 6 Load Load Load Load Load Load M M M M Main pump M M eat supply ydraulic separation NO YES NO YES YES YES Temperature control NO YES NO YES YES YES Investment LOW MEDIUM MEDIUM IG IG IG Operation cost llow LOW LOW LOW IG IG 168

9 Theory MIXING LOOPS SYSTEM 1 Function: Secondary side: The load will normally be an exchanger, where the temperature out of the exchanger is the set point. The flow is decreasing when the valve is closing. The valve can be placed either in the flow pipe or in the return pipe. Primary side: The flow is decreasing when the valve is closing If an uncontrolled pump is installed on the primary side, the differential pressure in the connection point will increase when the flow is decreasing. t = Constant = Variable T Load Interaction with speed controlled pump: M Primary side: The pump will reduce the speed when the valve is closing. Normally proportional pressure control is recommended in systems where the pressure lost is split between the pipe system and the control valves. Connection point ead Main system Closing valve Open valve Flow 169

10 FLOW TINKING Theory MIXING LOOPS SYSTEM 2 Function: Secondary side: The load will normally be a heat surface or a radiator system, where there is a demand for a variable temperature. The flow in the secondary side will normally be higher, due to a reduction in the flow temperature.the flow can be constant or variable, depending on the system. The valve can be placed either in the flow pipe or in the return pipe. Primary side: The flow is decreasing when the valve is closing. If an uncontrolled pump is installed on the primary side, the differential pressure in the connection point will increase when the flow is decreasing. Interaction with speed-controlled pumps: Secondary side: Due to the higher flow in the secondary side a speed controlled pump will have the authority in the secondary system. t = Variable = Constant = Variable T Load M Primary side: The pump will reduce the speed when the valve is closing. Normally proportional pressure control is recommended in systems where the pressure loss is split between the pipe system and the control valves. Connection point Main system ead Closing valve Open valve Flow 170

11 Theory MIXING LOOPS SYSTEM 3 Function: Secondary side: The load will normally be an exchanger, where the temperature out of the exchanger is the setpoint. The flow is decreasing when the valve is closing. The valve can be placed either in the flow pipe or in the return pipe. The pressure lost in the bypass has to be close to the same as the pressure lost in the system. Primary side: The flow is constant, but the differential temperature will change when the valve is adjusting. Interaction with speed-controlled pumps: t = Constant = Variable T Load B A AB M Primary side: A pressure-controlled pump will not react when the valve is adjusting, but it is possible to speed control the pump due to temperature, constant return temperature or constant differential temperature. = Constant Connection point Main system ead Port A or Port B Flow 171

12 FLOW TINKING Theory MIXING LOOPS SYSTEM 4 Function: Secondary side: The load will normally be a heat surface or a radiator system, where there is a demand for a variable temperature. Due to a reduction in the flow temperature, the flow in the secondary side will normally be higher. The flow can be constant or variable, depending on the system. The valve can be placed either in the flow pipe or in the return pipe. Primary side: The flow is decreasing when the valve is closing. If an uncontrolled pump is installed on the primary side, the differential pressure in the connection point will increase when the flow is decreasing. Interaction with speed-controlled pumps: Primary side: Due to the higher flow in the secondary side, a speed controlled pump will have the authority in the secondary system. Primary side: The pump will reduce the speed when the valve,is closing. Normally proportional pressure control is recommended in systems where the pressure loss is split between the pipe system and the control valves. t = Variable = Variable/ Constant M = Variable Connection point Load T AB B A Main system ead Closing valve AB-B Open valve AB-B Flow 172

13 Theory MIXING LOOPS SYSTEM 5 Function: Secondary side: The load will normally be a heat surface or a radiator system where there is a demand for a variable temperature. Due to a reduction in the flow temperature, the flow in the secondary side will normally be higher than in the primary side. The flow can be constant or variable, depending on the system. The valve can be placed either in the flow pipe or in the return pipe. t = Variable = Constant T Load Primary side: The flow is constant, but the differential temperature will change when the valve is adjusting. B A M Interaction with speed-controlled pumps: AB Secondary side: Due to the higher flow in the secondary side, the speed controlled pump will have the authority in secondary systems. Primary side: A pressure controlled pump will not react when the valve is adjusting, but it is possible to speed control the pump due to temperature, constant return temperature or constant differential temperature. = Constant Connection point Main system ead Port A or Port B Flow 173

14 FLOW TINKING Theory MIXING LOOPS SYSTEM 6 Function: Secondary side: The load will normally be a heat surface or a radiator system where there is a demand for a variable temperature. Due to a reduction in the flow temperature, the flow in the secondary side will normally be higher than in the primary side. The flow can be constant or variable, depending on the system. The valve can be placed either in the flow pipe or in the return pipe. Primary side: The flow is constant, but the differential temperature will change when the valve is adjusting. t = Variable = Constant T Load B AB A M Interaction with speed-controlled pumps: Secondary side: Due to the higher flow in the secondary side, a speed controlled pump will have the authority in secundary systems. = Constant Primary side: A pressure-controlled pump will not react when the valve is adjusting, but it is possible to speed control the pump due to temperature, constant return temperature or constant differential temperature. Connection point Main system ead Port A or Port B Flow 174

15 + 6. Tool box Theory MIXING LOOPS 3-way valves: 3-way valve for mixing Load 3-way valve for division Load Variable temperature Constant temperature Constant flow Variable flow AB A B B A AB Variable flow Constant flow Pressure control valves: Pressure relief Constant pressure M - p constant - + p constant Constant pressure Constant flow M Constant flow + - p constant

16 FLOW TINKING eating BASIC TEORY EAT LOSS The heating system should compensate for the heat loss in the building. Therefore this loss will be the basis for all calculations in connection with the heating system. t u The following formula should be used: U x A x (t i -t u ) = Φ Φ = The flow of heat (heat loss) in [W] U = The transmission coefficient in [W/m 2 K] A = The area in [m 2 ] t i = Dimensioning indoor temperature in [ C] t u = Dimensioning outdoor temperature in [ C] t i Flow in % = Variation in flow = Calculation profile CALCULATION OF FLOW When the heat flow Φ is known, the flow pipe temperature t F and the return-pipe temperature t R should be determined, in order to be able to calculate the volume flow rate. The temperatures not only determine the volume flow rate, but also when heating surfaces should be dimensioned (radiators, calorifiers etc.) The following formula should be used: Φ x 0.86 (t F -t R ) = t Operating hours in % Φ = eat demand in [kw] = Volume flow rate in [m 3 /h] t F = Dimensioning flow pipe temperature in [ C] t R = Dimensioning return-pipe temperature in [ C] 0.86 is the conversion factor (kcal/h to kw) t F t R 176

17 eating BASIC TEORY CALCULATION OF PRESSURE LOSS: To select the right pump and to have the right balance in the system, it is necessary to calculate the pressure lost in all parts of the system. A heating system can be devided into 3 parts: eat production: Boilers, eat exchangers, Solar collectors, Generators, etc. eat distribution: Pipes, Fittings, Valves, Pumps. eat consumption: Radiators, Calorifiers, eating surfaces, Fan coils, Floor heating coils Domestic hot water production. After dimensioning of the system, a pressure loss calculation should be made. The pressure loss (head) up to the critical point, i.e. the point to which the biggest pressure loss exists, should be the dimensioning pressure loss for the pump. If the system is big, it would be an advantage to zone-divide it, this would make the pressure loss calculation more clear. eat production eat production eat distribution eat consumption Zone 1 Zone 2 When zone-dividing the system, it is important to establish which components belong to the distribution part and which belong to the individual zone. After the calculation it is possible to draw a system characteristic in a coordinate system, where the pressure loss () is plotted on the Y-axis and the volume flow rate () on the X-axis. Normally the piping is dimensioned from a maximum pressure loss per m pipe, where Pa/m is a good basis. Another possibility is that the velocity of the pipes determines the dimensioning, up to 100 mm pipe = 1m/s (approx. 28m 3 /h). An economic pipe dimensioning should be made in cases of pipes over 100 mm. Main distribution Duty point Y-axis X-axis 177

18 FLOW TINKING eating BASIC TEORY STATIC PRESSURE: The static pressure of the system is the pressure which is not provided by the circulator pump. The static pressure depends on the construction of the system. We distinguish between 2 types of systems: Open system; Pressurized system. The static pressure has big influence on both pumps and valves. If the static pressure is too low, the risk of cavitation increases, especially at high temperatures. For canned rotor type pumps, a minimum inlet pressure (static pressure) is stated. For big pumps the static pressure can be calculated from the NPS value of the pump. Open system Atmospheric pressure Static system pressure Pressurized system Precompressed gas Static system pressure The height of the water level in the expansion tank gives the static pressure. In the shown example, the static pressure before the pump is approx. 1.6 m. Open systems are not used so often, but if the heat source for example is a solid fuel system, it may be required that the system is an open system. A pressurized system has a pressure expansion tank with a rubber membrane, which separates the compressed gas (nitrogen) and the water in the system. The static pressure of the system must be approx. 1.1 x the inlet pressure in the tank. If the static pressure is higher, the tank loses its ability to absorb the dilation of the water which happens when it is heated. This may cause unintentional pressure rises in the system. If the static pressure in the system is lower than the inlet pressure, there will be no water reserve when the temperature in the system falls, this may in some cases cause a vacuum in the system, and there is a risk of air being drawn in. Static system pressure Static pressure [m] Precompressed gas 178

19 Life Cycle Cost CALCULATION ELECTRICAL ENERGY Nearly 20 % of the world s electrical energy consumption is used for pump systems. In some Commercial Building Services pump systems the use of speed controlled pump systems makes it possible to save more than 50 % of this energy. 80% Other use 20% Pump systems STANDARD OF REFERENCE A Guide to LCC Analysis for Pumping Systems, is a referencebook on the LCC subject. It is the result of a collaboration between: ydraulic Institute Europump US Department of Energy s Office of industrial Technologies The life cycle cost of any piece of equipment is the total lifetime cost to purchase, install, operate, maintain and dispose of that equipment. The methodology to identify and quantify all of the components in the Life Cycle Cost will be described in the following section. COMPARISON When used as a comparison tool between possible design or overhaul alternatives, the LCC process will show the most cost-effective solution within the limits of available data. Euro Life Cycle Cost 10 years operation 0 System 1 System 2 Energy cost Maintenance 0 0 Initial Cost Initial Cost Maintenance Energy cost 179

20 FLOW TINKING Life Cycle Cost CALCULATION LCC EUATION The Life Cycle Cost is calculated as: LCC = C ic + C in + C e + C o + C m + C s + C env + C d Where: Typical Life Cycle Cost of a circulating system in Commercial Building Services LCC = life cycle cost C ic = inital costs, purchase price C in = installation and commissioning costs C e = energy costs C o = operation costs (labour cost) C m = maintenance and repair costs C s = down time costs (loss of production) C env = environmental costs C d = decommissioning/disposal costs In the following section each of these cost components will be described. As seen from the illustration, the energy cost, initial cost and maintenance cost are the most important in Commercial Building Services pump systems. Inital cost Maintenance cost Energy cost INITIAL COSTS, PURCASE PRICE (CIC) This includes all the equipment and accessories needed to operate the pump system. E.g. this includes: Pumps Frequency converters Control panels Transmitters Often there is a trade off between initial costs and energy and maintenance costs, as the more expensive components often have a longer lifetime or lower energy consumption as is the case with speed control pumps. Euro Example showing the initial costs Cic of a constant speed pump system (system 1) and a speed controlled pump system (system 2) System 1 System 2 Initial Cost Initial Cost 180

21 Life Cycle Cost CALCULATION INSTALLATION AND COMMISSIONING COSTS (C IN ) This includes costs such as: Installation of pumps Foundation (if necessary) Connection of electrical wiring and instrumentation Installation, connection and set-up of transmitters, frequency converters, etc. Connection to BMS system Performance eveluation at start-up Again it is advisable to check for trade offs. In some cases, as with speed controlled pumps, many components are integrated in the product, which then gives a higher initial cost, but lower installation and commisioning costs. Compared to other costs in a circulating Commercial Building Services pump system this kind of costs is often modest. Integrated components and software in an E-pump, which saves installation and commissioning costs User interface Software Control Frequency converter Standard motor ENERGY COSTS (C E ) Sensor In most cases, energy consumption is the largest cost in the LCC of pump systems in Commercial Building Services, where the pumps are often running more than 2000 hours a year. Many factors influence the energy consumption of the pump system, e.g.: Load profile Use of speed controlled solutions Pump efficiency (calculation of duty point should be carried out carefully) Motor efficiency (the motor efficiency at partial load can vary significantly between high efficiency motors and normal efficiency motors) Pump sizing (often margins and round up s tend to suggest oversized pumps) Other system components, such as pipes and valves Outdoor temperature C Pump Load profile of circulation systems in Commercial Building Services systems eating needs Cooling needs ours/year North European Central European South European 181

22 FLOW TINKING Life Cycle Cost CALCULATION OPERATING COSTS (C O ) Operating costs are labour costs related to the operation of a pumping system. In most cases the labour cost, which can be related to the pumps in a commercial building, is modest. Grundfos E-pumps provide various ways of monitoring the pump, e.g. the surveillance of the pumps can be done via the BMS, as the pumps have BUS communication. BMS Main station Secondary stations BUS Boiler room Technical college Other Gateway Components Pump Valve Pump MAINTENANCE AND REPAIR COSTS (C M ) This basically covers all costs related to maintenance and repair of the pump system, e.g.: Labour cost Spare parts Transportation Cleaning To obtain the optimum working life of a pump and prevent breakdowns, it is feasible to carry out routine maintenance. Grundfos has made some estimates on the cost of maintenance for the pumps. Wet-runner pumps are maintenancefree for a period of 10 years. Dry-runner pumps are estimated to have replaced the shaft seal three times and motor bearings four times during their life time, which is 20 years. This is estimated to a total of appr EUR per pump. 182

23 Life Cycle Cost CALCULATION DOWNTIME AND LOSS OF PRODUCTION COSTS (C S ) These costs are only relevant in pump systems used in production processes. In Commercial Building Services a stop of the pump rarely results in loss of production, but more in a loss of comfort. So the measureable cost of this is modest in CBS. But the unmeasureable costs, e.g. guests in a hotel without water can be even higher. Even though one pump is enough for the required pump performance, Grundfos always recommends to install a back-up pump, to prevent the loss of comfort caused by an unexpected failure in the pump system. The communication possibilities of the E-pumps make it possible to act fast in case of a break-down. ead [m] = 1 pump + 1 stand-by pump (wet runner) = 1 pump + 1 stand-by pump (Dry runner) = 2 pumps + 1 stand-by pump (dry runner) = 3 pumps + 1 stand-by pump (dry runner) , , ,000 10,000 Flow [m³/h] ENVIRONMENTAL COSTS (C ENV ) This includes the cost of disposal of parts and contamination from the pumped liquid. The contribution to the life cycle cost of a pump system in CBS from this is set to be modest. DECOMMISSIONING AND DISPOSAL COSTS (C D ) These costs are also more relevant in systems with harzardous liquids, and they seem to be non-existent or modest in CBS systems. At least there will be little difference occuring from the design of the system. 183

24 FLOW TINKING Life Cycle Cost CALCULATION CALCULATING LCC The LCC of a pump system is then made up of the summation of all the components over the life time of the system. This is typically years. As we are considering a significant amount of years, the most correct way of calculating LCC would be based on the discounted cash flow. Working with a time frame of these years also indicates that the energy price will probably be significantly higher than today. For political reasons, the price of energy is probably going to increase more than the general inflation. Where: Cp = Cn [ 1 + (i p ) ] n n = number of years p = expected annual inflation i = interest rate i p = real discount rate Cn = cost paid after n years Cp = present cost of a single cost element Cn The table on the following page can be used for keeping hold of the different cost components for a pump system or the comparison of two alternative systems. 184

25 Life Cycle Cost CALCULATION Alternative 1 Alternative 2 Input Initial investment cost Energy price (present) per kwh: Weighted average power of equipment in kw: Average operating hours per year: Energy cost per year (calculated) = Energy price x weighted average power x average operating hours per year: Maintenance cost (routine maintenance per year) Repair every 2nd year: Other yearly costs: Down time cost per year: Environmental cost: Decommissioning/disposal (Salvage) cost Life time in years: Interest rate, %: inflation rate, %: Output Present LCC value: Following the design guides in this System Guide generally tends to minimise the LCC of a pump system in CBS. The Grundfos consultants are always ready to dicuss the possibilities of lowering the LCC of a particular system. 185

26 FLOW TINKING Life Cycle Cost EXAMPLE SITUATION DESCIPTION A new office building is being designed. One of the evaluation criteria from the investor is energy consumption. Three alternative pump systems have to be evaluated. The need for circulating water in the heating system is calculated as: Total heat demand = kw Sizing flow = m³/h Sizing head = 45 m SYSTEM ONE Two constant speed pumps + one constant speed standby pump. ON/OFF operation. Selected pumps: 3 x NK /409 Motor size 3 x 200 kw ENERGY CALCULATION: Flow ours Effect Energy [%] [h] [kw] [kwh] The pumps are with ON/OFF control eat source Total Total

27 Life Cycle Cost EXAMPLE SYSTEM TWO Three speed controlled pumps + one speed controlled standby pump. Constant pressure control (measured over the pumps) Selected pumps: 4 x NK /400 Motor size 4 x 132 kw ENERGY CALCULATION: Flow ours Effect Energy [%] [h] [kw] [kwh] , , , ,000 Total Total 1.364,370 SYSTEM TREE Three speed controlled pumps + one speed controlled standby pump. Proportional pressure control (measured at suitable place in the system) Selected pumps: 4 x NK /400 Motor size 4 x 132 kw p control measured directly over the pumps eat source eat source p p control measured out in the system p 187

28 FLOW TINKING Life Cycle Cost EXAMPLE ENERGY CALCULATION: Flow ours Effect Energy [%] [h] [kw] [kwh] Total Total CALCULATING LCC AND SAVINGS 20 year operation time System 1 % System 2 % System 3 % Saving 1 vs. 3 % Remarks EURO LCC EURO LCC EURO LCC EURO Saving Saving between 1 and 3 C ic ,2% ,5% ,8% % End user price C in ,1% ,1% ,2% % Commissioning C e ,6% ,1% ,6% % Energy price 0,1 EURO/kWh C o 0 C m ,1% ,2% ,3% 0 0% New shaft seals/ motor bearings C s 0 C en 0 C d ,1% ,1% ,1% 0 LCC % % % % 188

29 Life Cycle Cost EXAMPLE CALCULATING LCC AND SAVINGS Life Cycle Cost 20 years operation Euro x System 1 System 2 System 3 Initial Cost Maintenance Energy cost Initial Cost Maintenance Energy cost PAYBACK TIME Overview of the payback time Euro x ,50 3,00 2,50 2,00 1,50 1,00 0,50 System 1 System 2 System Year of operation Payback time 189

30 FLOW TINKING Control mode OVERVIEW Control mode overview Control mode System type Constant curve Constant diff. pressure Proportional pressure (calculated) Proportional pressure (measury) Temperature control Constant flow Constant pressure Single pipe heating systems OX X Systems with 2 way valve OX O X Systems with 3 way valve OX X X eat and colling surfaces OX X Cooling towers X Chiller pumps OX X X Flow filter DW recirculation X Pressure boosting X O= Series 2000 product range X= Series 1000 product range 190

31 Control mode CONSTANT CURVE WERE TO USE When there is a demand for constant flow and constant head, a speed controlled pump can replace a throttle valve for adjusting the flow. The speed can be adjusted between 25% and 100%. This feature is specially benefitial in e.g. eat surfaces Cooling surfaces eating systems with 3 way valves Air-con system with 3 way valves Chiller pumps PUMP TYPES [%] RPM 100% 90% 80% 70% 60% 50% 25% [%] Series 2000 UPE(D)/TPE Series 1000 TPE(D)/LME(D)/LPE(D)/CLME NBE/NKE ACCESSORIES Effect in % Single speed pump Remote control R100 (Series 1000) 20 Constant curve operation Flow in % OW TO USE Duty point with valve Duty point without valve M din. dim. 191

32 FLOW TINKING Control mode CONSTANT DIFF. PRESSURE WERE TO USE Used in circulating systems with a pipe system with low pressure drop and control valves to generate a variable flow. The pressure drop in the control valves is higher than 50% of the total pressure drop. eating systems with 2 way valves Air-con system with 2 way valves (only TPE Series 2000) [%] RPM 100% 90% 80% 70% 60% 50% 25% PUMP TYPES [%] Series 2000 UPE(D)/TPE Series 1000 TPE(D)/LME(D)/LPE(D)/CLME NBE/NKE Single speed pump ACCESSORIES Remote control R100 (Series 1000) Effect in % Diff. pressure controlled 20 OW TO USE Flow in % p Exchanger 3,5 m M M M p control valve 6 m as to be kept constant Total p pump 11 m p Pipe system 1,5 m 192

33 Control mode PROPORTIONAL PRESSURE (CALCULATED) WERE TO USE Used in circulation systems with a pipe system with low pressure drop and control valves to generate a variable flow. The pressure drop in the control valves is lower than 50% of the total pressure drop. eating systems with 2 way valves Air-con system with 2 way valves (only TPE Series 2000) PUMP TYPES Series 2000 UPE(D)/TPE [%] RPM 100% 90% 80% 70% 60% 50% 25% [%] ACCESSORIES Remote control R100 (optional) Single speed pump Effect in % Diff. pressure controlled OW TO USE Flow in % p Exchanger 3,5 m p control valve 1,5 m as to be kept constant Total p pump 11 m p Pipe system 6 m 193

34 FLOW TINKING Control mode PROPORTIONAL PRESSURE (MEASURED) WERE TO USE Mostly used in circulation systems with an extensive pipe system and control valves to generate a variable flow. The pressure drop in the control valves is lower than 50% of the total pressure drop. [%] RPM 100% 90% eating systems with 2 way valves District heating net Air-con system with 2 way valves 80% 70% 60% 50% PUMP TYPES Series 1000 TPE(D) LME(D LPE(D) CLME NBE/NKE % Single speed pump [%] 80 ACCESSORIES Remote control R100 Differential presure transmitter Effect in % Diff. pressure controlled OW TO USE Flow in % M M M M p 194

35 Control mode TEMPERATURE CONTROL WERE TO USE Circulation systems without control valves to generate a variable flow and systems where it is important to have a constant temperature e.g. Single pipe heating system Boiler shunts eating systems with 3 way valves Air-con system with 3 way valves Domestic hot water circulation [%] RPM 100% 90% 80% 70% 60% 50% 25% PUMP TYPES [%] Series 1000 TPE(D)/LME(D)/LPE(D)/CLME NBE/NKE ACCESSORIES Single speed pump Remote control R100 Temperature transmitter or Differential temperature transmitter OW TO USE Effect in % Flow in % Temp./diff. temp. controlled Single pipe system with return temperature transmitter 195

36 FLOW TINKING Control mode CONSTANT FLOW WERE TO USE Circulation systems without control valves to generate a variable flow and systems where it is important to have a constant temperature e.g. Single pipe heating system Boiler shunts eating systems with 3 way valves Air-con system with 3 way valves Domestic hot water circulation [%] RPM 100% 90% 80% 70% 60% 50% 25% PUMP TYPES [%] Series 1000 TPE(D)/LME(D)/LPE(D)/CLME NBE/NKE ACCESSORIES Single speed pump Remote control R100 Flow transmitter or Differential pressure transmitter OW TO USE Effect in % Flow/diff. 20 pressure controlled Flow in % Using a P transmitter for constant flow. Knowing the characteristic of a constant resistance it is possible to lay down the exact P giving the right flow P Pump set point Demand flow 196

37 Control mode CONSTANT PRESSURE WERE TO USE Circulation systems without control valves to generate a variable flow and systems where it is important to have a constant temperature e.g. Single pipe heating system Boiler shunts eating systems with 3 way valves Air-con system with 3 way valves Domestic hot water circulation [%] RPM 100% 90% 80% 70% 60% 50% 25% PUMP TYPES [%] Series 1000 TPE(D)/LME(D)/LPE(D)/CLME NBE/NKE ACCESSORIES Single speed pump Remote control R100 Flow transmitter Diff. pressure transmitter Effect in % Pressure controlled 20 OW TO USE Flow in % Pressure holding Pressure boosting p p 197