3 Functions of Wilo pumps
3.1 Application based control modes
Finding the optimal control mode for a specific application is often not a simple, straight-forward task. By contrast, the pump’s prospective application is known. This serves as a simple orientation for the configuration based on this application. Wilo pumps include a number of standard and new control modes in order to guarantee optimal pump operation in every application. The control modes can be divided into the following basic groups:
- Pressure control modes, such as Δp-v, Δp-c, Dynamic Adapt Plus
- Volume flow control modes, such as Q-const
- Fluid temperature control modes, such as ΔT-const or T-const
- Hall temperature control modes
In addition to these basic control modes, a range of additional functions can also be activated: Q-Limit, No-Flow Stop, etc. The control modes are described in detail in the following.
3.2 Application heating
The properly selected pump ensures a countinous and sufficient colume flow in generator circuits, distribuion circuis as well as in consumer circuits. It avoids unintend noise and reduces nergy costs.
3.2.1 Heating: Radiator consumer circuit
The pump is installed in a consumer circuit that supplies a static heating system with radiators. The Δp-v, Dynamic Adapt plus or T-const constant hall temperature control modes could be selected for this application.
3.2.1.1 Pressure control
If the heating circuit supplies multiple rooms, the radiators will be fitted with control valves to regulate the individual rooms’ temperatures. In this case, Δp-v (nominal delivery head setting required) or Dynamic Adapt plus (nominal delivery head setting not required) could be selected. For this application, Wilo recommends the Dynamic Adapt plus control mode.
3.2.1.2 Hall temperature control modes
If the heating circuit supplies heat to a large thermal zone, e.g. a hall, the control valves on the radiators are redundant or are not present in an existing building. The pump can then directly regulate the hall temperature to the desired setpoint using the T-const constant hall temperature control mode. In addition, it is necessary to install a temperature sensor or a room user interface in the hall to measure the temperature and act as a setpoint controller. These values are transmitted to the pump via the analogue inputs. The temperature sensor to measure the actual temperature can either be connected directly as a PT1000 sensor or as an active sensor with 0…10 V and 4…20 mA. The setpoint can be transmitted as a 0…10 V or 4…20 mA signal. If a setpoint controller is not installed in the room, the setpoint can also be set in the pump as a fixed value.
3.2.2 Heating: Underfloor heating consumer circuit
The pump is installed in a consumer circuit that supplies a slow surface heating system, e.g. underfloor heating. The basic control modes Δp-c, Dynamic Adapt plus or T-const constant hall temperature can be used for this application.
3.2.2.1 Pressure control
If the heating circuit supplies multiple rooms, the radiators will be fitted with control valves to regulate the individual rooms’ temperatures. In this case, Δp-c (nominal delivery head setting required) or Dynamic Adapt plus (nominal delivery head setting not required) could be selected. For this application, Wilo recommends the Dynamic Adapt plus control mode.
3.2.2.2 Hallentemperaturregelung
If the heating circuit supplies heat to a large thermal zone, e.g. a hall, the control valves on the underfloor heating’s distributor connections are redundant and are often not present in existing buildings. The pump can then directly control the temperature to reach the desired setpoint using the T-const constant hall temperature control mode. In addition, it is necessary to install a temperature sensor or a room user interface in the hall to measure the temperature and act as a setpoint controller. These values are transmitted to the pump via the analogue inputs. The temperature sensor to measure the actual temperature can either be connected directly as a PT1000 sensor or as an active sensor with 0…10 V and 4…20 mA. The setpoint can be transmitted as a 0…10 V or 4…20 mA signal. If a setpoint controller is not installed in the room, the setpoint can also be set in the pump as a fixed value.
3.2.3 Heating: Ceiling heating consumer circuit
The pump is installed in a consumer circuit that supplies a ceiling heating. The control modes Δp-c, Dynamic Adapt plus or T-const constant hall temperature can be used for this application.
3.2.3.1 Pressure control
If the heating circuit supplies multiple rooms, the ceiling heating circuits will be fitted with control valves to regulate the individual rooms’ temperatures. In this case, Δp-c (nominal delivery head setting required) or Dynamic Adapt plus (nominal delivery head setting not required) could be selected. For this application, Wilo recommends the Dynamic Adapt plus control mode.
3.2.3.2 Hall temperature control modes
If the heating circuit supplies heat to a large thermal zone, e.g. a hall, the control valves on the ceiling heating’s distributor connections are redundant and are often not present in existing buildings. The pump can then directly regulate the hall temperature to the desired setpoint using the T-const constant hall temperature control mode. In addition, it is necessary to install a temperature sensor or a room user interface in the hall to measure the temperature and act as a setpoint controller. These values are transmitted to the pump via the analogue inputs. The temperature sensor to measure the actual temperature can either be connected directly as a PT1000 sensor or as an active sensor with 0…10 V and 4…20 mA. The setpoint can be transmitted as a 0…10 V or 4…20 mA signal. If a setpoint controller is not installed in the room, the setpoint can also be set in the pump as a fixed value.
3.2.4 Heating: Fan heater consumer circuit
The pump is installed in a consumer circuit that supplies very fast air heating, e.g. a fan heater. The Δp-v, Dynamic Adapt plus or T-const constant hall temperature control modes could be selected for this application.
3.2.4.1 Pressure control
If the heating circuit supplies multiple rooms, the radiators will be fitted with control valves to regulate the individual rooms’ temperatures. In this case, Δp-v (nominal delivery head setting required) or Dynamic Adapt plus (nominal delivery head setting not required) could be selected. For this application, Wilo recommends the Dynamic Adapt plus control mode.
3.2.4.2 Hall temperature control modes
If the heating circuit supplies heat to a large thermal zone, e.g. a hall, the control valves on the fan heaters are redundant and are often not present in existing buildings. The pump can then directly regulate the hall temperature to the desired setpoint using the T-const constant hall temperature control mode. In addition, it is necessary to install a temperature sensor or a room user interface in the hall to measure the temperature and act as a setpoint controller. These values are transmitted to the pump via the analogue inputs. The temperature sensor to measure the actual temperature can either be connected directly as a PT1000 sensor or as an active sensor with 0…10 V and 4…20 mA. The setpoint can be transmitted as a 0…10 V or 4…20 mA signal. If a setpoint controller is not installed in the room, the setpoint can also be set in the pump as a fixed value.
3.2.5 Heating: Generator or feeder circuit with hydronic separator
The pump is installed in a generator or feeder circuit that supplies a hydraulic shunt with heat. Hydraulic shunts are installed to hydraulically decouple two systems. In this context, a distinction must be made between two objectives:
- The feed temperature is to be set on the secondary side. This is the case, for example, for underfloor heating circuits which are supplied by a high-temperature distributor. To do this, the volume flow on the primary side must be reduced accordingly in relation to the secondary side. The Stratos MAXO provides the fluid temperature control function for this purpose.
- The energy is to be transferred without raising the return temperature if at all possible. In this case, it is necessary to adjust the volume flow on the primary side according to that on the secondary side. The Stratos MAXO provides the ΔT and Multi-Flow Adaptation functions for this purpose.
3.2.5.1 Temperature control: Constant secondary feed temperature T-const
The feed temperature behind the hydraulic shunt (secondary side) is regulated to the defined setpoint by adjusting the speed of the pump in front of the shunt. It is also necessary to install a temperature sensor (PT1000 or active sensor with 0…10 V and 4…20 mA output) in the secondary feed. The pump is connected via one of the two analogue inputs.
3.2.5.2 Temperature control: ΔT-const between primary side return flow and secondary side return flow
The temperature difference between the hydraulic shunt primary and secondary return flows is controlled to reach the defined setpoint. The volume flow in the primary circuit is thereby aligned with the secondary volume flow. It is therefore necessary to install two temperature sensors (PT1000 or active sensor with 0…10 V and 4…20 mA output) in the primary and secondary return flows. The connection to the pump is made via the two analogue inputs.
3.2.5.3 Multi-Flow Adaptation
Mit der Regelungsart Multi-Flow Adaptation wird der Volumenstrom im Erzeuger- bzw. Zubringerkreis (Primärkreis) an den Volumenstrom in den Verbraucherkreisen (Sekundärkreis) angepasst. Multi-Flow Adaptation wird an der Wilo-Stratos MAXO Zubringerpumpe im Primärkreis vor der hydraulischen Weiche eingestellt. Die Wilo-Stratos MAXO Zubringerpumpe ist mit den Wilo-Stratos MAXO Pumpen in den Sekundärkreisen per Datenkabel verbunden. Die Zubringerpumpe erhält von jeder einzelnen Sekundärpumpe fortlaufend in kurzen Zeitabständen den jeweils erforderlichen Volumenstrom. Die Summe der erforderlichen Volumenströme von allen Sekundärpumpen stellt die Zubringerpumpe als Soll-Volumenstrom ein. Bei der Inbetriebnahme müssen dafür alle zugehörigen Sekundärpumpen bei der Primärpumpe angemeldet werden, damit diese deren Volumenströme berücksichtigt. Die Verbindung der Pumpen per Wilo Bus-System Wilo Net ist im Kapitel 4.2.6 näher beschrieben. Für nicht kommunikationsfähige Sekundärpumpen kann ein fester Volumenstrombedarf angegeben werden, um auch diese zu berücksichtigen. Ebenso lässt sich ein Korrekturfaktor an der Zubringerpumpe einstellen, der eine zusätzliche Versorgungssicherheit bietet.
3.2.6 Heating: Generator or feeder circuit with heat exchanger
The pump is installed in a generator or feeder circuit (primary circuit) that supplies a heat exchanger with heat. Heat exchangers are installed to separate two hydraulic systems and transfer thermal energy from one system to another. In this context, a distinction must be made between two objectives:
- The feed temperature is to be set on the secondary side. This is the case, for example, in an underfloor heating circuit which is supplied from one distributor along with static heating circuits. To do this, the volume flow on the primary side must be reduced accordingly. The Stratos MAXO provides the fluid temperature control function for this purpose.
- The energy is to be transferred without raising the return temperature if at all possible. In this case, it is necessary to adjust the volume flow on the primary side according to that on the secondary side. The Stratos MAXO provides the ΔT and Multi-Flow Adaptation functions for this purpose.
3.2.6.1 Temperature control: Constant secondary feed temperature T-const
The feed temperature behind the heat exchanger (secondary side) is regulated to the defined setpoint by adjusting the speed of the pump upstream of the heat exchanger (primary side). It is also necessary to install a temperature sensor (PT1000 or active sensor with 0…10 V and 4…20 mA output) in the secondary feed. The pump is connected via one of the two analogue inputs.
3.2.6.2 Temperature control: ΔT-const between primary side feed and secondary side feed
The temperature difference between the heat exchanger’s primary and secondary feeds is controlled to reach the defined setpoint. The volume flow in the primary circuit is thereby aligned with the secondary volume flow. It is therefore necessary to install a temperature sensor (PT1000 or active sensor with 0…10 V and 4…20 mA output) in both the primary and secondary feeds. The sensors in the pump can be used for the primary side, meaning that the temperature sensor is connected to the pump on the secondary side. The connection to the pump is made via the two analogue inputs.
3.2.6.3 Multi-Flow Adaption
With the Multi-Flow Adaptation control mode, the volume flow in the generator/feeder circuit (primary circuit) is aligned with the volume flow in the consumer circuits (secondary circuit). Multi-Flow Adaptation is set in the Stratos MAXO feeder pump in the primary circuit upstream of the heat exchanger. The Stratos MAXO feeder pump is connected to the Stratos MAXO pumps in the secondary circuits via a data cable. The feeder pump continuously receives the respective required volume flow from each individual secondary pump in short intervals. The sum of the required volume flows from all secondary pumps is set by the feeder pump as the target volume flow. On commissioning, all associated secondary pumps must be connected to the primary pump so that it can take their volume flows into consideration. A fixed volume flow requirement can be entered for non-communicationcapable secondary pumps so that their flows are also taken into consideration.
3.3 Application domestic hot water
Pumps used in domestic hot water circulation are subjet to special requirements which are fullfilled by the -Z models of the selected pump. All plastic parts in contact fith the fluid are compliant with the german KTW remoomendations. All metallc parts in contact with the fluid are compliant to the narmative and regulative requirements.
3.3.1. Domestic hot water: circulation
The pump is installed as a circulator. The T-const control mode can be used for this application in order to enable safe, hygienic operation.
3.3.1.1
The pump in the circulation line changes its speed so that the water returning to the tank is always at the desired specified warm water temperature. The temperature sensor for this purpose is located in the pump. A separate sensor is not necessary.
3.3.2 Domestic hot water: storage tank
3.3.2.1 Temperaturregelung
The pump is controlling the differential temperature between forward and return pipe to a desired setpooint ΔT=2…50 K. The pump conveyes exactly the volume flow whic is needed to maintain the setpoint. Therefore, the installation of up to two temperature sensors (PT1000 or active type with voltage or current output) is required in the forward and return circuit. If the pump provides an internal sensor, it can be used for either forward or return temperature. For the proper configuration, T1 must be the (higher) forward temperature and T2 the (lower) return temperature while the setpoint &DeltaT is equal to T1-T2.
3.4 Application cooling
Korrosionsfreie Pumpenausführung
3.4.1 Cooling: Ceiling cooling consumer circuit
The pump is installed in a consumer circuit that supplies fast surface cooling, e.g. a cooling ceiling or ceiling canopy. The control modes Δp-c, Dynamic Adapt plus or T-const constant hall temperature can be used for this application.
3.4.1.1 Druckregelung
If the cooling circuit supplies multiple rooms, the cooling area circuits will be fitted with control valves to regulate the individual rooms’ temperatures. In this case, Δp-c (nominal delivery head setting required) or Dynamic Adapt plus (nominal delivery head setting not required) could be selected. For this application, Wilo recommends the Dynamic Adapt plus control mode.
3.4.1.2 Hall temperature control modes
If the cooling circuit cools a large thermal zone, e.g. a hall, the control valves on the ceiling cooling’s distributor connections are redundant and are often not present in existing buildings. The pump can then directly regulate the hall temperature to the desired setpoint using the T-const constant hall temperature control mode. In addition, it is necessary to install a temperature sensor or a room user interface in the hall to measure the temperature and act as a setpoint controller. These values are transmitted to the pump via the analogue inputs. The temperature sensor to measure the actual temperature can either be connected directly as a PT1000 sensor or as an active sensor with 0…10 V and 4…20 mA. The setpoint can be transmitted as a 0…10 V or 4…20 mA signal. If a setpoint controller is not installed in the room, the setpoint can also be set in the pump as a fixed value.
3.4.2 Cooling: Underfloor cooling consumer circuit
The pump is installed in a consumer circuit that supplies slow surface cooling, e.g. underfloor cooling. The control modes Δp-c, Dynamic Adapt plus or T-const constant hall temperature can be used for this application.
3.4.2.1 Pressure control
If the cooling circuit supplies multiple rooms, the cooling area circuits will be fitted with control valves to regulate the individual rooms’ temperatures. In this case, Δp-c (nominal delivery head setting required) or Dynamic Adapt plus (nominal delivery head setting not required) could be selected. For this application, Wilo recommends the Dynamic Adapt plus control mode.
3.4.2.2 Hall temperature control modes
If the cooling circuit cools a large thermal zone, e.g. a hall, the control valves on the underfloor cooling’s distributor connections are redundant and are often not present in existing buildings. The pump can then directly regulate the hall temperature to the desired setpoint using the T-const constant hall temperature control mode. In addition, it is necessary to install a temperature sensor or a room user interface in the hall to measure the temperature and act as a setpoint controller. These values are transmitted to the pump via the analogue inputs. The temperature sensor to measure the actual temperature can either be connected directly as a PT1000 sensor or as an active sensor with 0…10 V and 4…20 mA. The setpoint can be transmitted as a 0…10 V or 4…20 mA signal. If a setpoint controller is not installed in the room, the setpoint can also be set in the pump as a fixed value.
3.4.3 Kühlen: Cooling: Air-conditioning device consumer circuit
The pump is installed in a consumer circuit that supplies very fast air cooling, e.g. an air-conditioning device. The control modes Δp-v, Dynamic Adapt plus or T-const constant hall temperature can be used for this application.
3.4.3.1 Pressure control
If the cooling circuit supplies multiple rooms, the airconditioning device will be fitted with control valves to regulate the individual rooms’ temperatures. In this case, Δp-v (nominal delivery head setting required) or Dynamic Adapt plus (nominal delivery head setting not required) could be selected. For this application, Wilo recommends the Dynamic Adapt plus control mode.
3.4.3.2: Hall temperature control modes
If the cooling circuit cools a large thermal zone, e.g. a hall, the control valves on the air-conditioning devices are redundant and are often not present in existing buildings. The pump can then directly regulate the hall temperature to the desired setpoint using the T-const constant hall temperature control mode. In addition, it is necessary to install a temperature sensor or a room user interface in the hall to measure the temperature and act as a setpoint controller. These values are transmitted to the pump via the analogue inputs. The temperature sensor to measure the actual temperature can either be connected directly as a PT1000 sensor or as an active sensor with 0…10 V and 4…20 mA. The setpoint can be transmitted as a 0…10 V or 4…20 mA signal. If a setpoint controller is not installed in the room, the setpoint can also be set in the pump as a fixed value.
3.4.4 Heating: Generator or feeder circuit with hydronic separator
The pump is installed in a generator or feeder circuit that supplies a hydraulic shunt with refigerated water. Hydraulic shunts are installed to hydraulically decouple two systems. In this context, a distinction must be made between two objectives:
- The feed temperature is to be set on the secondary side. This is the case, for example, for underfloor cooling circuits which are supplied by a chiller. To do this, the volume flow on the primary side must be reduced accordingly in relation to the secondary side. The selected pump provides the fluid temperature control function for this purpose.
- The energy is to be transferred without raising the return temperature if at all possible. In this case, it is necessary to adjust the volume flow on the primary side according to that on the secondary side. The selected pump provides the ΔT and Multi-Flow Adaptation functions for this purpose.
3.4.4.1 Temperature control: Constant secondary feed temperature T-const
The feed temperature behind the heat exchanger (secondary side) is regulated to the defined setpoint by adjusting the speed of the pump upstream of the heat exchanger (primary side). It is also necessary to install a temperature sensor (PT1000 or active sensor with 0…10 V and 4…20 mA output) in the secondary feed. The pump is connected via one of the two analogue inputs.
3.4.4.2 Temperature control: ΔT-const between primary side feed and secondary side feed
The temperature difference between the heat exchanger’s primary and secondary feeds is controlled to reach the defined setpoint. The volume flow in the primary circuit is thereby aligned with the secondary volume flow. It is therefore necessary to install a temperature sensor (PT1000 or active sensor with 0…10 V and 4…20 mA output) in both the primary and secondary feeds. The sensors in the pump can be used for the primary side, meaning that the temperature sensor is connected to the pump on the secondary side. The connection to the pump is made via the two analogue inputs.
3.4.4.3 Multi-Flow Adaptation
With the Multi-Flow Adaptation control mode, the volume flow in the generator/feeder circuit (primary circuit) is aligned with the volume flow in the consumer circuits (secondary circuit). Multi-Flow Adaptation is set in the Stratos MAXO feeder pump in the primary circuit upstream of the heat exchanger. The Stratos MAXO feeder pump is connected to the Stratos MAXO pumps in the secondary circuits via a data cable. The feeder pump continuously receives the respective required volume flow from each individual secondary pump in short intervals. The sum of the required volume flows from all secondary pumps is set by the feeder pump as the target volume flow. On commissioning, all associated secondary pumps must be connected to the primary pump so that it can take their volume flows into consideration. A fixed volume flow requirement can be entered for non communication capable secondary pumps so that their flows are also taken into consideration.
3.4.5 Heating: Generator or feeder circuit with heat exchangerKühlen: Erzeuger- oder Zubringerkreispumpe mit Wärmetauscher
The pump is installed in a generator or feeder circuit (primary circuit) that supplies a heat exchanger with chilled water. Heat exchangers are installed to separate two hydraulic systems and transfer thermal energy from one system to another. In this context, a distinction must be made between two objectives:
- The feed temperature is to be set on the secondary side. This is the case, for example, for underfloor cooling circuits which are supplied by a chiller. To do this, the volume flow on the primary side must be reduced accordingly in relation to the secondary side. The selected pump provides the fluid temperature control function for this purpose.
- The energy is to be transferred without lowering the return temperature if at all possible. In this case, it is necessary to adjust the volume flow on the primary side according to that on the secondary side. The selected pump provides the ΔT and Multi-Flow Adaptation functions for this purpose.
3.4.5.1 Temperature control: Constant secondary feed temperature T-const
The feed temperature behind the heat exchanger (secondary side) is regulated to the defined setpoint by adjusting the speed of the pump upstream of the heat exchanger (primary side). It is also necessary to install a temperature sensor (PT1000 or active sensor with 0…10 V and 4…20 mA output) in the secondary feed. The pump is connected via one of the two analogue inputs.
3.4.5.2 Temperature control: ΔT-const between primary side feed and secondary side feed
The temperature difference between the heat exchanger’s primary and secondary feeds is controlled to reach the defined setpoint. The volume flow in the primary circuit is thereby aligned with the secondary volume flow. It is therefore necessary to install a temperature sensor (PT1000 or active sensor with 0…10 V and 4…20 mA output) in both the primary and secondary feeds. The sensors in the pump can be used for the primary side, meaning that the temperature sensor is connected to the pump on the secondary side. The connection to the pump is made via the two analogue inputs.
3.4.5.3 Multi-Flow Adaption
With the Multi-Flow Adaptation control mode, the volume flow in the generator/feeder circuit (primary circuit) is aligned with the volume flow in the consumer circuits (secondary circuit). Multi-Flow Adaptation is set in the Stratos MAXO feeder pump in the primary circuit upstream of the heat exchanger. The Stratos MAXO feeder pump is connected to the Stratos MAXO pumps in the secondary circuits via a data cable. The feeder pump continuously receives the respective required volume flow from each individual secondary pump in short intervals. The sum of the required volume flows from all secondary pumps is set by the feeder pump as the target volume flow. On commissioning, all associated secondary pumps must be connected to the primary pump so that it can take their volume flows into consideration. A fixed volume flow requirement can be entered for non-communication capable secondary pumps so that their flows are also taken into consideration.
3.5 Basic control modes
In addition to the option of selecting the control mode based on the application, the basic control modes can also be directly adjusted. This is the case, for example, when the required settings for the field of application are already known (e.g. in the case of pump replacement) or if none of the pump’s predefined applications are suitable for the specific installation. The basic control modes are freely configurable and can be individually adjusted to the application by the user. They can also be combined with numerous additional options. In this case, it must be checked that the pump functions correctly.
For the selected pump the following control functions are available:
- Differential pressure Δp-c
- Differential pressure Δp-v
- Δp-c with remote sensor
- Dynamic Adapt plus
- Temperature T-const.
- Temperature ΔT-const.
- Volume flow Q-const.
- Multi-Flow Adaptation
- Rotational speed n-const.
- PID control
3.5.1 Differential pressure Δp-c
In Δp-c control mode, the pump keeps the differential pressure it generates constant at the set differential pressure setpoint Hsetpoint throughout the permissible volume flow range up to the maximum pump curve. The required differential pressure from the pipe network calculation Hn corresponds to the setpoint Hsetpoint. Fields of application e.g.:
- Consumer circuit with underfloor heating (heating) or underfloor/ceiling vents (cooling) in which pressure fluctuations through valves are very low compared to the pressure loss in the pipe network
3.5.2 Differenzdruck Δp-v
In the Δp-v control mode, the pump linearly varies the differential pressure setpoint to be maintained between the specified Hsetpoint on the maximum pump curve and ½ Hsetpoint at zero volume flow. The setpoint Hsetpoint does not generally correspond to the required differential pressure from the pipe network calculation, and must instead be identified using the nominal duty point and Qnominal. The duty point (nominal volume flow and delivery head) can be directly specified using the additional “Nominal duty point” function. Control properties: The pump variably adjusts the required volume flow according to the opened and closed valves on the consumers, thereby adjusting the power required. It saves electrical pumping energy in comparison to Δp-c. The setpoint is defined using the duty point, which can usually be taken from the pipe network calculation. Fields of application e.g.:
- Consumer circuit with radiators and fan heaters (heating) or air-conditioning devices (cooling)
With the auxiliary function "Δp-v slope", the gradient of the head variation by the volume flow can be adjusted.
3.5.3 Δp-c with remote sensor
In the index circuit Δp-c control mode, the pump keeps the differential pressure at a remote point in the pipe network (index circuit) constant at the set differential pressure setpoint Hs throughout the permissible volume flow range up to the maximum pump curve. The required differential pressure from the pipe network calculation Hn corresponds to the setpoint Hs.A differential pressure sensor is installed at the index circuit and connected to the pump as an actual value sensor via an analogue input. The nominal differential pressure to be maintained at the index circuit must be specified. Control properties: Just as for Δp-c, the nominal delivery head must be specified that applies precisely to the remote point in the network. An index circuit evaluation continuously monitors the sensor’s pressure difference at the critical point in the pipe network. Fields of application e.g.:
- Primary side of a local heat supply up to the transfer station to the connected buildings
- Extensive existing systems with unknown hydraulic properties
3.5.4 Dynamic Adapt plus
The pump automatically adjusts the delivery head to the hydraulic demand without the need to specify a setpoint. After initial commissioning, the pump selects a duty point in the middle of the pump duty chart. New operating points are identified after each change in volume flow. The aim of this control method is to select the operating point so that the valves are open as wide as possible. This allows the system to operate with the lowest possible pressure loss. Control properties: The delivery head does not need to be specified. The pump automatically and independently adapts to variable pressure conditions. Electrical pumping energy savings of up to 20 % are possible in comparison to Δp-v. The performance range extends across almost the entire pump duty chart. Fields of application e.g.:
- Consumer circuits with variable volume flows, e.g. radiators with thermostatic valves, underfloor heating with individual room controls, cooling ceilings or air-conditioning devices
3.5.5 Temperature T-const
In the T-const control mode, the pump keeps the temperature constant at a specified setpoint. In the positive effective direction, the pump increases its speed if the actual temperature is lower than the setpoint temperature. In the negative effective direction, speed decreases. The effective direction and the controller’s amplification factors can be individually adjusted by selecting the basic control mode without selecting the application. A temperature sensor is installed to transmit the current temperature e.g. in the feed to the secondary circuit. These values are transmitted to the pump via the analogue inputs. The temperature sensor can either be connected directly as a PT1000 sensor or as an active sensor with 0…10 V and 4…20 mA. Control properties: Independent of the differential pressure, the pump provides the exact volume flow required to maintain the specified setpoint temperature. Fields of application e.g.:
- Supply of a consumer circuit with a fixed feed temperature
- Versorgung eines Verbraucherkreises mit einer festen Vorlauftemperatur
3.5.6 Temperature ΔT-const.
In the ΔT const control mode, the pump maintains a constant temperature difference setpoint. In the positive effective direction, the pump increases its speed if the actual temperature difference is higher than the setpoint temperature difference. In the negative effective direction, speed decreases. The effective direction and the controller’s amplification factors can be individually adjusted by selecting the basic control mode without selecting the application. Two temperature sensors are installed to transmit the current temperature e.g. in the primary and secondary circuit feeds. These values are transmitted to the pump via the analogue inputs. The temperature sensors can either be connected directly as PT1000 sensors or as active sensors with 0…10 V and 4…20 mA. Control properties: Independent of the differential pressure, the pump provides the exact volume flow required to maintain the specified setpoint temperature difference. Fields of application e.g.:
- Supply of a consumer circuit with a fixed temperature difference
3.5.7 Volume flow Q-const.
In der Regelungsart konstanter Volumenstrom Q-const. hält die Pumpe einen eingestellten Volumenstrom-Sollwert konstant. Dazu erhöht sie die Drehzahl im zulässigen Bereich, falls der gemessene Volumenstrom kleiner ist als der Sollwert und umgekehrt. Regelungseigenschaften: Der gewünschte Volumenstrom wird konstant eingehalten, unabhängig vom Differenzdruck. Einsatzbereiche z. B.:
- Erzeugerkreis einer Wärmepumpe ohne geregelten Inverter, um eine Heizleistung fest einzuhalten
- Rückkühlkreis mit Rückkühlwerk mit konstanter Leistung
3.5.8 Multi-Flow Adaptation
The Multi-Flow Adaptation control mode is applicable for a Stratos MAXO feeder pump in the primary circuit that, for example, supplies an open distributor, a hydraulic shunt or a heat exchanger. The feeder pump is connected to the Stratos MAXO pumps in the secondary circuits via a data cable. The feeder pump continuously receives the respective required volume flow from each individual secondary pump in short intervals. The sum of the required volume flows from all secondary pumps is set by the feeder pump as the target volume flow. On commissioning, all associated secondary pumps must be connected to the primary pump so that it can take their volume flows into consideration. A fixed volume flow value can be entered for non communication capable secondary pumps. Control properties: The feeder pump provides exactly as much volume flow as is required by the secondary pumps. It therefore saves electrical pumping energy in comparison to Δp-c control. The heat generator’s degree of utilisation is optimised by a lower return temperature. This leads to fuel savings. For local and district heating transfer stations, the lower return temperature leads to higher operational reliability, as it avoids activating the return temperature limiter as well as overflows. Field of application e.g.:
- Pumps in district heating transfer stations without controllersthat supply distributors with secondary pumps
- Feeder pumps that supply open distributors or heat exchangers with secondary pumps with no speed control through the heat generator
Einsatzbereich z. B.:
- Pumpen in Fernwärmeübergabestationen ohne Ansteuerung durch einen Regler, die auf Verteiler mit Sekundärpumpen fördern
- Zubringerpumpen, die ohne Drehzahl-Ansteuerung durch den Wärmeerzeuger auf offene Verteiler oder Wärmetauscher mit Sekundärpumpen fördern
3.5.9 Rotational speed n-const.
In the constant speed n control mode, the pump control keeps constant at the specified speed setpoint. Control properties: The speed setpoint is usually specified via an external signal, e.g. via 0 – 10 V. The setpoint always remains the same unless changed based on demand. Field of application e.g.:
- Control of the selected pump by a boiler controller via the 0 – 10 V signal.
3.5.10 PID control
In the PID control mode, the pump keeps constant at a defined setpoint by means of a PID controller. This setpoint could be a temperature, a pressure or any other physical value. A signal value transmitted via one of the pump’s analogue inputs can be used as the actual value. The effective direction of the controller and its amplifications factors P, I and D can be individually adjusted according to the application. Control properties: The pump’s P, I and D factors are set on the basis of individual, specific requirements. Advanced knowledge of control technology is required to make configurations. Field of application e.g.:
Configuration of temperature sensors
The following table shows the standard configuration of the temperature sensors for the selected control mode. Whereever possible, PT1000 sensors are used.
| Function | Sensor source | Sensor type |
|---|---|---|
| Forward temperature (Tf) | internal sensorAnalog input AI3 analog input AI2 choose control mode | PT1000 |
| Return temperature (Tr) | analog input AI2 AI4 internal sensor choose control mode | PT1000 |
| process value (T1) | internal sensor analog input AI1 analog input AI2AI4 je nach Anwendung | PT1000U/I PT1000 |
| process value (T2) | analog input (AI1) internal sensor depending on application | PT1000 |
Pump control with the mode choosen above
| Function | Register | Value |
|---|---|---|
| Function | Object | Value |
| Control mode | Holding Register 42 | 17 (DA+) 16 (Δp-v) 18 20 (DA+) 19 (Δp-c) 21 23 (DA+) 22 (Δp-c) 24 26 (DA+) 25 (Δp-v) 27 28 29 30 31 32 33 67 68 44 (DA+) 43 (Δp-c) 45 47 (DA+) 46 (Δp-c) 48 50 (DA+) 49 (Δp-c) 51 52 53 54 55 56 57 3 4 79 80 9 10 81 82 1 140 choose control function |
| Control mode | Multistate Output 0 | 17 (DA+) 16 (Δp-v) 18 20 (DA+) 19 (Δp-c) 21 23 (DA+) 22 (Δp-c) 24 26 (DA+) 25 (Δp-v) 27 28 29 30 31 32 33 67 68 44 (DA+) 43 (Δp-c) 45 47 (DA+) 46 (Δp-c) 48 50 (DA+) 49 (Δp-c) 51 52 53 55 56 6 7 79 80 9 10 81 82 1 13 choose control function |
| pump on/off | Binary Output 0Holding Register 40 | 1/09/8 |
| setpoint | Analog Output 0Holding Register 1 |
control sequence:
- select normal parameter set to ensure that following datapoints are effective (writing value of 1 to Multistate Output 34Holding Register 416)
- check if normal parameter set was adopted (reading Multistate Input 2034Input Register 211) - if not, write the readout value first, then the desired one
- select control function (writing Multistate Output 0Holding Register 42)
- check if control function was adopted (reading Multistate Input 0Input Register 10) - if not, write the readout value first, then the desired one
- select setpoint signal source to fieldbus (writing value of 1 to Multistate Output 3Holding Register 401)
- check if setpoint signal source was adopted (reading Multistate Input 3Input Register 210) - if not, write the readout value first, then the desired one
- physical unit can be determined from Multistate Input 33Input Register 208
- scale desired setpoint to this physical unit
- divide the scaled value by value from Analog Input 33Input Register 206 (100 % value): this is the relative setpoint
- range can be checked by comparison with the limits Analog Input 32Input Register 202 (max.) & Analog Input 31Input Register 204 (min.)
- write relative setpoint to: Analog Output 0Holding Register 1
N.B.: Some control modes (e.g. dynamic adapt plus) do not require a setpoint. Therfore the setpoint limits & the 100% values contain the error value. This indicates that writing a setpoint is not required / possible.
Example conversion:
- pump type: Stratos MAXO 40/0,5-4 (differential pressure 0.5 m up to 4 m water column): control mode Δp-c
- physical unit read from pump: bar
- 100 % value read from pump: 0,392266 ( 1 m water column equivalent 0,0980665 bar; 0,392266 equivalent 4 m water column)
- relative duty point minimum read from pump: 12.5 % ( equivalent 0.5 m water column)
- relative duty point maximum read from pump: 100 % ( equivalent 4 m water column) (is mostly 100 % with some exceptions for negative range of setpoint)
- assumed desired duty point: 2.5 m water column
- equivalent to 0.24516625 bar (scaled to target physical unit)
- relative duty point = 0.24516625 / 0.392266
- relative duty point = 0.625 (62.5 %) (this value shall be written)
Status indication
The pump provides the following status information:
- pump ready (also set if running) Binary Input 9Input Register 404 Bit0
- pump running Binary Input 10Input Register 404 Bit1
- service required Binary Input 11Input Register 404 Bit2
- warning Binary Input 12Input Register 404 Bit3
- error Binary Input 13Input Register 404 Bit4
- final error Binary Input 14Input Register 404 Bit5
- error/event code (matches code on display)Fehler/Eventcode (identisch mit Code auf dem Display) Multistate Input 4Input Register 901
- error/event codeFehler/Eventcode Multistate Input 1Input Register 940
The device may also be a twin head/double pump. There it may be possible that "pump ready" and "error" status are set at the same time.
Logging: generate a log entry at every change on "pump ready", "service required", "warning", "error" or "final error". The error/event code should also be logged to provide the details
process data
While status information can discover issues with the pump itsself, the process values may discover problems caused by the process. Display of process data is most meaningful when done together with the functional limits (min/max values)
| value | current | min | max |
|---|---|---|---|
| volume flow | Analog Input 2Input Register 2 | Analog Input 51Input Register 25 | Analog Input 50Input Register 24 |
| (differential) pressure | Analog Input 3Input Register 1 | — | Analog Input 14Input Register 20 |
| electrical power | Analog Input 4Input Register 4 | — | Analog Input 15Input Register 28 |
| rotational speed | Analog Input 1Input Register 7 | Analog Input 8Input Register 19 | Analog Input 9Input Register 18 |
| power heating | Analog Input 20Input Register 300 | — | — |
| power refrigeration | Analog Input 21Input Register 302 | — | — |
| forward temperature | Analog Input 16Input Register 316 | — | — |
| return temperature | Analog Input 17Input Register 318 | — | — |
Visualization of statistics data
| value | current |
|---|---|
| energy heating | Analog Input 26Input Register 312 |
| energy refrigeration | Analog Input 27Input Register 314 |
| energy electrical | Analog Input 7Input Register 3 |
| operation time | Analog Input 6Input Register 5 |
3.6 Additional functions for the control modes
The subsequent functions can be activatated by writing a valid value from the fieldbus. Writing the error value will de-activate the function.
3.6.1 No Flow Stop Analog Output 38Holding Register 424 / Analog Input 38Input Register 274
The pump recognises when, despite its speed, the flow rate supplied is too low. This means that the valves in the consumer circuit are closed. The pump stops the motor if the volume flow falls below a specified minimum level. The pump then checks at regular intervals whether the minimum volume flow has been exceeded again. As soon as this occurs, the pump continues in its set control mode in auto control mode.
Benefit:
Electrical pumping energy is saved by avoiding unnecessary running times.
Field of application e.g.:
- A pump in a consumer circuit with radiators, fan heaters, underfloor or ceiling vents in heating or cooling mode, as an additional function for all control modes except Multi-Flow Adaptation
3.6.2 Automatic detection of setback operation
The pump detects a significant reduction in fluid temperature over a defined period of time. The pump thereby deduces that the heat generator is in setback operation. The pump independently reduces its speed until a high fluid temperature is once again detected over a longer period of time. This leads to savings in electrical pumping energy.
Benefit:
Electrical pumping energy is saved by avoiding unnecessary running times.
Field of application e.g.:
- A pump in a heat generator circuit in control modes Δp-v or Δp-c supplying a system with radiators or fan heaters
- A pump in heat generator circuits in control mode T-const or ΔT-const
- A pump in a consumer circuit with radiators or fan heaters in control modes Dynamic Adapt plus or Δp-v
3.6.3 Nominal duty point in Δp-v control
The additional function of a nominal duty point can be used together with Δp-v. Instead of the delivery head on the maximum pump curve, the nominal duty point can be entered directly. This is made up of the nominal volume flow and the nominal delivery head. Both values can usually be taken from the pipe network calculation and are often provided on the heating or cooling schematics in the pump list. Pump control automatically calculates a suitable pump curve that runs through the nominal duty point.
Benefit:
If known, the desired duty point can be precisely specified.
Field of application:
- A pump in a consumer circuit with radiators or fan heaters in control mode Δp-v
3.6.4 Slope of the Δp-v curve
This additional function may be used together with the Δp-v based control functions. For an optimized control characteristics, the reduction factor for the delivery head at no volume flow can be adjusted. Depending on the pipework, supply may be not optimized with the standard factor of 50 %.
Benefit:
With the adaption of the reduction factor energy savings can be raised.
3.6.5 Q-Limitmin (minimum volume flow limit) Analog Output 36Holding Register 422 / Analog Input 36Input Register 272
The Q-Limit Min function can be used in conjunction with all control modes except Dynamic Adapt plus and constant volume flow Q-const. The pump will not fall below the specified minimum volume flow limit within the permitted range, independent of the delivery head.
Benefit:
Pump is adjusted precisely according to demand
Field of application:
- Ensuring the minimum volume of circulation water in a heat generator
3.6.6 Q-Limitmax (maximum volume flow limit) Analog Output 37Holding Register 420 / Analog Input 37Input Register 270
The Q-Limit Max function can be used in conjunction with all control modes except Dynamic Adapt plus and constant volume flow Q-const. The specified maximum volume flow limit is not exceeded by the pump control within the permitted range, independent of the delivery head.
Benefit:
Pump is adjusted precisely according to demand. Additional components such as differential pressure valves or mixers are not required.
Field of application:
- A pump in a heat generator circuit and a storage charge pump: Limit the maximum volume flow to boiler output in the event of low pipeline resistance
- Local/district heating: Limit the maximum volume flow of the pump on the secondary side because the maximum permitted volume flow is available on the primary side (supply side). (Return temperature is thereby kept low)
3.6.7 Switching between heating/cooling
If the selected pump is installed in a circuit used for both heating and cooling, the pump can switch between heating or cooling depending on the current application. This is achieved by an external binary contact or by detecting the feed temperature. If the feed temperature is over e.g. 25 °C, the pump enters heating mode with the corresponding control mode setting (e.g. Dynamic Adapt plus). If the feed temperature is below e.g. 19 °C, it operates in the applicable setting (e.g. Δp-c). Between 19 °C and 25 °C, the pump starts up at regular intervals to identify whether cooling or heating is required. 19 °C and 25 °C are the preconfigured values, but other settings can be made.
Benefit:
Nutzen:
The pump is individually adjusted to ensure optimal energy transfer in heating or cooling mode. The pump itself identifies the current application. The heating/cooling quantity required from the pump is identified separately.
Fields of application e.g.:
Einsatzbereiche z. B.:
- A heat generator pump downstream of a three-way valve that supplies a cold water generator and a heat generator
- A pump in the consumer circuit of a reversible heat pump that both heats and cools
- A consumer rotary pump that supplies both hot and cold water for e.g. concrete core activation or ceiling vents
3.6.8 Erkennung thermische Desinfektion
The domestic hot water circulator uses a sensor connected to the hot water tank or the hot water output line to detect when the hot water temperature exceeds a specified limit value. It detects that thermal disinfection has been started and thus continues to supply at full speed. A pipe surface contact sensor mounted on the hot water discharge line must also be connected to the pump.
Benefit:
Nutzen:
Reduction of rapid cooling of hot water in the pipe network and improvement of the thermal disinfection effect by ensuring proper flushing using a high volume flow.
Fields of application e.g.:
Einsatzbereiche z. B.:
- Domestic hot water circulator in hot water systems in which regular thermal disinfection is required
3.7 Data collection functions
3.7.1 Heating/cooling quantity measurement
The heating/cooling quantity is measured through volume flow detection in the pump and temperature detection in the feed or return. The Stratos MAXO has a precise fluid temperature sensor which can detect one of the two temperatures (depending on whether the pump is installed in the feed or return). As a result, only one further temperature sensor is required and should be connected to the pump. An application-based pump configuration must be conducted for heating and cooling respectively. The pump can switch over to heating or cooling either automatically or as instructed by an external signal. The heating and cooling quantity is identified separately based on the application.
Benefit:
Nutzen:
An energy measurement for heating and cooling can be conducted without an additional energy meter. The measurement can be used for the internal distribution of heating and cooling costs or for system monitoring. However, as the heating and cooling measurement is not calibrated, it cannot be used as the basis for billing.
Field of application:
Einsatzbereiche z. B.:
- Internal billing of energy flows
- System and energy monitoring
- System optimisation
| Funtion | Register |
|---|---|
| energy heating (resetable) | Analog Input 22Input Register 304 |
| energy refrigeration (resetable) | Analog Input 24Input Register 308 |
| energy heating (total) | Analog Input 26Input Register 312 |
| energy refrigeration (total) | Analog Input 27Input Register 314 |
| power heating | Analog Input 20Input Register 300 |
| power refrigeration | Analog Input 21Input Register 302 |
| forward temperature | Analog Input 16Input Register 316 |
| return temperature | Analog Input 17Input Register 318 |
3.7.2 Recording of historical data
The selected pump is capable to record data during the daily operation. All data is recorded with the timestamp:
- pump head
- volume flow
- rotational speed
- forward and return temperatures
- hall temperature (if used for control)
- heating and refrigeration energy
- electrical power consumption
- temperature of the electronics
- operation hours
- number of air venting sequences
- history of envents
The historical data of a specific period of time can be displayed with the Wilo Smart Connect
3.8 Pump functions independent of the control mode
3.8.1 Double pump management
The selected pump can be operated either with two single pumps or as a double pump variant with double pump management. The double pump variant is fully wired-up upon delivery and is configured as a double pump. Only one of the two pump modules has a fully functional LCD colour display. The second pump module is equipped with a 7-segment LED display. If two single pumps in the Y-piece are operated as a double pump, both single pumps must be set to double pump mode on commissioning. Cabling between the pumps for double pump operation must also be completed during installation and commissioning. The following operating modes are possible due to the intelligent double pump management system with one -D double pump or two single pumps:
Main/standby operation
Haupt-/Reservebetrieb
If the version-specific pump output is provided by one pump, the other pump remains available on standby for time-actuated switchover (24 hours of pure operating time) or fault-actuated switchover. Standby operation can be performed by all double pumps and all single pumps (2 x identical type).
Parallelbetrieb
Parallel operation
If the version-specific pump output is provided by both pumps in parallel operation, power adjustments are made through synchronous operation of both pumps. Parallel operation can be performed by all double pumps and all single pumps (2 x identical type).
Note: both operation modes require only one CIF-module in the master pump
3.8.4. Temperature sensor (internal)
A temperature sensor is mounted in the pump housing. The immersed sensor measures the temperature of the fluid passing the pump. For various control modes T-const. or ΔT-const, this sensor can be used as reference. The digital interface of the sensor is connected via a detachable cable to the pump. The measured value is shown in the display of the pump.
Further sensors can be connected to the analog inputs or provided via BAS
Hinweis:
Hint:
If high precision of closed loop control is required and/or the effective temperature difference is low, the usage of PT1000 AA sensors is recommended.
3.9 Acessories
3.9.7 CIF-Module for integration into BAS
For the integration into a building automation system (BAS), a communication interface module is used. The following variants are available:
- CIF-Modul Ethernet Multiprotokoll (2211408) - today with BACnet/IP and Modbus TCP
- CIF-Modul BACnet MS/TP (2190367)
- CIF-Modul Modbus RTU (2190368)
- CIF-Modul Modbus LON TP/FT-10 (2190370)
- CIF-Modul Modbus CANopen (2190369)
- CIF-Modul PLR (2190371)