Configure Plants

 
Configure Plants
The Configure Plants screen allows for modification of the plant that was just created. Each loop can be individually modified by adding or removing equipment and controls based on the specific configuration. Only modification of the supply side of each loop can be done in this section. The supply side of the loop contains rules for placement of components so that the simulation is allowed to run successfully. You will also have the ability to modify each specific component within the loop as well as the overall properties of the loop for sizing purposes. In order to move on from this screen, all loops must be configured with components and there should be no validation error messages.
 
Plant Component Selection Bar
The selection bar allows for inputting equipment into the plant diagram. For each component there are set rules for equipment placement depending on the loop type. The component selection displays categories of components that can be added to a loop. These categories are:
 
Each loop type will display the categories and components that are valid. Click on the category button to expand it and view the components that can be added to the loop. Select a component on the bar by clicking on it. The plant diagram will highlight the valid locations for placing the component on the loop. To drop a component on the plant diagram, click on one of the green dot locations.
Below is a description of each category:
 
Pumps
The Pumps category in the Component Selection Bar displays the valid pump types that can be added to the loop.  The available pumps for all loop types are shown below. For more information on each type of equipment see the Equipment Library.
 
       Constant Volume Pump Not-Headered
       Variable Volume Pump Not-Headered
       Constant Volume Pump Headered
       Variable Volume Pump Headered
 
Pumps that have been added to a loop will be displayed in the Properties Section under Components. Each component displays information from the equipment library member that has been selected. The library member may be changed but its information is not editable, but the values entered in the fields in the Components tab will override the library values. The fields displayed for pumps are:
       Name
       Full Load Energy
       Pump Head
       Motor Efficiency
       Motor Heat to Fluid
       Flow Control
 
 
 
Equipment
The Equipment category in the Component Selection Bar displays the valid component types that can be added to each loop type. The available equipment per Loop Type is shown below. For more information on each type of equipment see the Equipment Library
 
·        Chilled Water Loop
§        Air Cooled Chiller
§        Water Cooled Chiller
§        Absorption Chiller
§        Engine Driven Air Cooled Chiller
§        Engine Driven Water Cooled Chiller
§        District Cooling
§        Temperature Source
·        Hot Water Loop
§        Boiler
§        Water Heater
§        District Heating
§        Temperature Source
·        Condenser Loop
§        Cooling Tower
§        Fluid Cooler
§        Evaporative Fluid Cooler
§        Well
·        Mixed Water Loop
§        Boiler
§        Water Heater
§        District Heating
§        Temperature Source
§        Cooling Tower
§        Fluid Cooler
§        Evaporative Fluid Cooler
§        District Cooling
§        Ground Heat Exchanger
§        HX w/ Controls
·        Heat Exchanger Loop
§        Chilled Water Loop to Chilled Water HX
o       Air Cooled Chiller
o       Water Cooled Chiller
o       Absorption Chiller
o       Engine Driven Air Cooled Chiller
o       Engine Driven Water Cooled Chiller
o       District Cooling
o       Temperature Source
§        Chilled Water Loop to Mixed Water HX
o       Air Cooled Chiller
o       Water Cooled Chiller
o       Absorption Chiller
o       Engine Driven Air Cooled Chiller
o       Engine Driven Water Cooled Chiller
o       District Cooling
o       Temperature Source
§        Hot Water Loop to Mixed Water HX
o       Boiler
o       Water Heater
o       District Heating
o       Temperature Source
§        Hot Water Loop to Hot Water HX
o       Boiler
o       Water Heater
o       District Heating
o       Temperature Source
§        Condenser Water Loop to Condenser Water HX
o       Air Cooled Chiller
o       Water Cooled Chiller
o       Absorption Chiller
o       Engine Driven Air Cooled Chiller
o       Engine Driven Water Cooled Chiller
o       District Cooling
o       Temperature Source
§        Condenser Water Loop to Chilled Water HX
o       Cooling Tower
o       Fluid Cooler
o       Evaporative Fluid Cooler
o       Well
§        Condenser Water Loop to Mixed Water HX
o       Cooling Tower
o       Fluid Cooler
o       Evaporative Fluid Cooler
o       Well
§        Mixed Water Loop to Hot Water HX
o       Boiler
o       Water Heater
o       District Heating
o       Temperature Source
o       Cooling Tower
o       Fluid Cooler
o       Evaporative Fluid Cooler
o       Ground Heat Exchanger
o       HX w/controls
§        Mixed Water Loop to Chilled Water HX
o       Boiler
o       Water Heater
o       District Heating
o       Temperature Source
o       Cooling Tower
o       Fluid Cooler
o       Evaporative Fluid Cooler
o       District Cooling
o       Ground Heat Exchanger
·        VRF Loop
§        VRF Outdoor Unit
§        Water VRF Outdoor Unit
 
 
 
 
Heat Exchanger
The Heat Exchanger category in the Component Selection Bar displays the valid component types that can be added to each loop type. The available equipment per Loop Type is shown below. For more information on each type of equipment see the Equipment Library. 
·        Chilled Water Loop
§        HX w/controls
§        HX Waterside Economizer
·        Hot Water Loop
§        HX w/controls
·        Condenser Loop
§        HX w/controls
·        Mixed Water Loop
§        HX w/controls
·        Heat Exchanger Loop
§        Chilled Water Loop to Chilled Water HX
o       HX w/controls
o       HX Waterside Economizer
§        Chilled Water Loop to Mixed Water HX
o       HX w/controls
o       HX Waterside Economizer
§        Hot Water Loop to Mixed Water HX
o       HX w/controls
§        Hot Water Loop to Hot Water HX
o       HX w/controls
§        Condenser Water Loop to Condenser Water HX
o       HX w/controls
o       HX Waterside Economizer
§        Condenser Water Loop to Chilled Water HX
o       HX w/controls
§        Condenser Water Loop to Mixed Water HX
o       HX w/controls
§        Mixed Water Loop to Hot Water HX
o       HX w/controls
§        Mixed Water Loop to Chilled Water HX
o       HX w/controls
 
 
Controls and Sensors
 For Loops, the only available control is a Water Temperature Set Point Controller. This controller can be connected to components added to the loop to sense the water temperature in that node. The control strategy can then be defined in the Properties Section of the Controls tab. 
  
Validation Messages
Validation will be done every time equipment is dropped into the diagram as well as when properties are changed. The validation messages will show warnings or fatal errors within that particular plant section. Validation can be done by clicking the magnifying glass underneath the demand box. Once clicked, it will provide you with an explanation on why the loop did not validate and how to correct the issue. Each loop has special validation rules written. 
 
Sequencing
Plants and condenser loops must have a mechanism for controlling the operation of the loop and controlling which equipment is available under different operating conditions. Once the loop load is calculated by the return conditions from the demand side and using the loop set point, this load needs to be allocated to the supply equipment according to the inputs. This can be done by using the sequencing button shown on the diagram. 
 
 
There are several different sequencing types which can be controlled on an hourly basis throughout the year. The sequencing types are discussed in the Sequencing properties section.
 
Demand Loads
This input is used for when building loads are already known. Demand load, flow rates, and schedule are specified in this section. This can be used for cooling and heating loads.
When entering a demand load in either a cooling or heating plant, enter the load as positive in either case and the correct sign convention will be assigned by the software. 
When entering a demand load in a mixed water loop, enter heating loads as negative and cooling loads as positive. 
The inputs related to demand loads are discussed in the Demand Load Properties section.
 
Configure Plant Tree Features
The Configure Plants tree will function and look identical to the tree shown in the Select Plants tree, but now you can edit the properties of the components, not just read them. The edit (pencil) button will appear next to the loop or component when it is selected. The edit button will take you to the properties screen. Right clicking on a component or loop in the tree will allow for renaming. 
 
 
 
Plant Diagram
 
The plant diagram is a graphic representation of a loop. It displays the supply side components as well as a demand box. As components are selected in the component selection bar, the plant diagram will highlight valid placement locations with green dots. To drop a component on the plant diagram, click on one of the green dot locations. To delete a component from the plant diagram, click to select the component and hit delete. As components are added to the plant diagram, they will be added to the equipment of the properties section.
 Each loop type in the Loop Library has business rules that will help create a valid loop configuration. When you are finished configuring your plant, click the validation button (magnifying glass) to display Validation Messages that will help you fix invalid configurations or missing data. 
  
Demand Side or Demand Box
The plant demand side contains equipment that places a load on the primary equipment. This might include coils, baseboards, radiant systems, etc. .
 
Within the demand section, if you are using the Plant Wizard or are located in the Assign Loops section, you can view supply side components that the demand is connected to. An example would be a condenser loop that is connected to one or multiple chillers. 
 
 
These assignments or connections can be viewed by clicking on the component or loop that it is connected to.  
 
Supply Side
Supply side will contain primary equipment, such as chillers or boilers, on the supply side loop. Each supply side must be connected to a demand side and vice versa. You can select components by using the plant component selection bar. Each component has rules associated to them on where they can be placed within the diagram. Each valid location will have a green dot for placement. If the component location breaks a rule, then the validation rules will appear and will give a suggestion on what to fix in the particular loop. 
 
  
 
 
Properties
 
The properties section of plants allows you to view and configure the sizing and control parameters of the plant loops or components within the plant loops.
Properties can be accessed by:
  • highlighting a component in the Plant Diagram and hitting the properties button in the bottom left, or
  • highlighting a component or loop in the tree and then clicking the edit button next to the component or loop.
 
In all properties, the top will have a breadcrumb which shows which loop, component or template you are highlighted on. You can navigate to other loops by selecting the loop and a drop down will appear.
 
Additionally, there will be several different tabs of the properties. These sections are:
 
 
 
 
 
Loop Sizing
 
Fluid Type
Default Value: Water
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: This field determines the type of fluid for the loop: Water, Ethylene Glycol, or Propylene Glycol. If Ethylene Glycol or Propylene Glycol is selected, the Glycol Concentration field becomes available. Ethylene Glycol or Propylene Glycol is used as an anti-freeze.
 
Input Considerations: If using ice storage tanks, select ethylene glycol or propylene glycol for the fluid type.
 
 
 
Glycol Concentration
Default Value: 30%
Min & Max: 0–100
Typical Range: 20–40
Units: %
 
Description: Only appears when Ethylene Glycol or Propylene Glycol is selected for the fluid type.  As an example, a mixture of 60% ethylene glycol and 40% water freezes at -49 degrees F.
 
Input Consideration: N/A
 
 
Loop Design Temperature Difference
Default Values: Cooling Loop 10 °F; Heating Loop 10 °F; Mixed Loop 10 °F; Condenser Loop 10 °F
Min & Max: -999 to 999
Typical Range: -999 to 999
Units: °F, °C
 
Description: This input is the design temperature rise (for cooling or condenser loops) or fall (for heating loops) across the demand side of a plant loop. The temperature difference is used to determine flow rates required to meet design capacities.
 
Input Considerations: A higher temperature difference results in lower flow rates.
 
 
 
Design Loop Exit Temperature
Default Values: Cooling Loop 44 °F; Condenser 95 °F; Mixed Loop 90 °F; Heating 180 °F
Min & Max: -999 to 999
Typical Range: 0–200
Units: °F, °C
 
Description: This input is the water temperature at the exit of the supply side of the plant loop (after supply components such as chillers, cooling towers, boilers, etc). Thus this is the temperature of the water supplied to the inlet of chilled or hot water coils and other equipment that places loads on a plant loop.
 
Input Considerations: A higher or lower than normal temperature may impact equipment performance.
 
 
 
Loop Sizing Method
Default Value: Block
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: This field controls how concurrence issues impact the plant loop design flow rate. There are two options:
 
o            Block - The cooling plant capacity is equal to the sum of the highest block load as simulated of the airside cooling coils as well as demand loads assigned to the cooling plant.
o            Peak - The cooling plant capacity is equal to the sum of the airside cooling coil capacities or demand loads assigned to the cooling plant.
Input Considerations: N/A
 
 
Block Sizing Timestep
Default Value: 1
Min & Max: 1–60
Typical Range: 1–4
Units: N/A
 
Description: This is the number of timesteps used in a moving average to determine the design flow rate for plant sizing. This allows using a broader average over time.
 
Input Considerations: If you want to size a plant based on a larger timestep (e.g. 1 hour versus 15 minute time step increments), you would enter in a value that would be greater than 1 here. A good example would be wanting to size a plant based on a 1 hour average versus a timestep for simulation which is 15 minutes. A number of 4 would be entered (15 * 4 = 60 minutes) to size the plant based on one hour.
 
 
Sizing Factor
Default Value: 100%
Min & Max: 100–999
Typical Range: 115%–120%
Units: N/A
 
Description: This is the factor to over or undersize the capacity of the loop. This is also more commonly known as a safety factor.
 
Input Considerations: N/A
 
 
 
 
Components
 
The Components tab displays the information of the components that have been added to a loop. The components will be displayed on a table grouped by the category from the Component selection bar: Pumps, Equipment, Thermal Storage, and Heat Exchanger. When expanded, each component will display pertinent information about the selected equipment library member. A different equipment library member can be selected, but the library member information cannot be edited on this screen.
 
All components except for Heat Exchangers and District Cooling/Heating are in the library. To view details on each input field, please go to the equipment library section to view them in more detail.
 
Heat Exchangers
 
A fluid-to-fluid heat exchanger is designed to couple the supply side of one plant or condenser loop to the demand side of another plant or condenser loop. This heat exchanger is fairly general and can be configured for use in any application where two loops need to be connected together. The only constraints are that one side must be connected to the supply side of one loop and the other side connected to the demand side of a different loop. Because the heat exchanger is intended to be generic, its two sides are distinguished by the type of loop side being connected. One side is called “Loop Supply Side” to indicate the heat exchanger is situated on the supply side of a loop. The other side is called “Loop Demand Side” to indicate it is on the demand side of a loop. The heat exchanger is intended to act as a supply component for the loop connected to it as the “Loop Supply Side” and as a demand component for the loop connected to it as the “Loop Demand Side.” From the point of view of the heat exchanger model itself, the Loop Demand Side fluid serves as the source/sink to supply heating/cooling to the fluid in the Loop Supply Side.
 
Model Type
Default Value: Ideal
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Below are the selection types for the model.
 
Cross Flow Both Unmixed:
Specifies a single-pass, cross-flow heat exchanger. The effectiveness will be calculated using a cross-flow heat exchanger correlation for both streams unmixed.
Cross Flow Both Mixed:
Specifies a single-pass, cross-flow heat exchanger. The effectiveness will be calculated using a cross-flow heat exchanger correlation for both streams mixed.
Cross Flow Supply Mixed
Demand Unmixed:
Specifies a single-pass, cross-flow heat exchanger. The effectiveness will be calculated using a cross-flow heat exchanger correlation for flow mixed on the Loop Supply side and flow unmixed on the Loop Demand Side.
Cross Flow Supply Unmixed
Demand Mixed:
Species a single-pass, cross-flow heat exchanger. The effectiveness will be calculated using a cross-flow heat exchanger correlation for flow unmixed on the Loop Supply side and flow mixed on the Loop Demand Side.
Counter Flow:
Specifies a counter-flow shell and tube heat exchanger. The effectiveness will be calculated using a counter-flow shell and tube heat exchanger correlation.
Parallel Flow:
Specifies a parallel-flow shell and tube heat exchanger. The effectiveness will be calculated using a parallel-flow shell and tube heat exchanger correlation.
Ideal:
Specifies an ideal heat exchanger. The effectiveness will be set to ‘1.0’ and the specified UA will be ignored. The heat transfer rate will be calculated as the maximum possible heat transfer rate.
 
 
UA Value
Default Value: Autosized
Min & Max: 0– no maximum
Typical Range: N/A
Units: N/A
 
Description: This numerical field is used to specify the overall U-Factor Times Area (UA) for use in the calculation of the heat exchanger effectiveness. If Ideal is specified as the heat exchanger type, the effectiveness will be set to 1.0. When set to autosize, the Heat Exchanger U-Factor Times Area value is calculated based on an effectiveness of 1.0, where capacity is such that the temperatures in the plant for the two loops can be maintained.
 
 
Control Type
Default Value:
For uncontrolled HX – Uncontrolled, For HX with Controls – Cooling Setpoint Modulated,
For HX Waterside Economizer – Waterside Economizer based on Differential Temperature
Min & Max:
0– N/A
Typical Range:
N/A
Units:
N/A
 
Description: This field is used to specify how the heat exchanger is to be controlled during operation. Varying applications for connecting two loops will require different control behavior and different control options are needed depending on the desired behavior. There are the following eleven key choice options to choose from:
 
For Heat Exchanger Uncontrolled, the options are:
o        Uncontrolled,
o        Sequencing with Modulated Flow, and
o        Sequencing with Max Flow
 
For Heat Exchanger with Controls, the options are:
o        Cooling Setpoint Modulated,
o        Cooling Setpoint On/Off,
o        Dual Deadband Setpoint Modulated,
o        Dual Deadband Setpoint On/Off,
o        Heating Setpoint Modulated, and
o        Heating Setpoint On/Off
 
For Heat Exchanger with Waterside Economizer, the options are Waterside Economizer based on Differential Temperature and Waterside Economizer Integrated with Chiller
 
o        Uncontrolled - This control mode is applicable to situations where the heat exchanger is passively running all the time and always transfers as much heat as possible between the fluid streams. However there is one aspect of control in that it will only request flow on the Loop Demand Side when there is non-zero flow into the heat exchanger on the Loop Supply Side.
o        Operation Scheme Modulated - This control mode is applicable to situations where the heat exchanger is controlled by an operation scheme. When using this control mode the heat exchanger serves as a supply component. The operation scheme will dispatch a load request to the heat exchanger which it will try meet by conditioning the fluid stream connected as the Loop Supply Side. If the heat exchanger could exceed the load request, then the flow through the fluid stream connected as the Loop Demand Side will be modulated to just meet the load request.
o        Operation Scheme On Off - This control mode is applicable to situations where the heat exchanger is controlled by an operation. When using this control mode the heat exchanger serves as a supply component. The operation scheme will dispatch a load request to the heat exchanger which it will use as an on/off signal to decide if the heat exchange should run or not. If it runs, it will run at full capacity and may exceed the load request.
o        Heating Setpoint Modulated - This control mode is applicable to situations where the Loop Demand Side can provide useful heating to the Loop Supply Side. If the setpoint and inlet temperatures are such that heat exchanger could transfer heat from the Loop Demand Side to the Loop Supply Side to meet the heating setpoint, then the heat exchanger will run. The inlet temperatures must differ by more than the value set in the field called Minimum Temperature Difference to Activate Heat Exchanger for the heat exchanger to operate. If the heat exchanger could overshoot the setpoint, then the flow through the fluid stream connected as the Loop Demand Side will be modulated to just meet the setpoint.
o        Heating Setpoint On/Off - This control mode is applicable to situations where the Loop Demand Side can provide useful heating to the Loop Supply Side. If the setpoints and inlet temperatures are such that heat exchanger could transfer heat from the Loop Demand Side to the Loop Supply Side to meet the heating setpoint, then the heat exchanger will run. The inlet temperatures must differ by more than the value set in the field called Minimum Temperature Difference to Activate Heat Exchanger for the heat exchanger to operate. If it runs, it will run at full capacity and may overshoot the setpoint.
o        Cooling Setpoint Modulated - This control mode is applicable to situations where the Loop Demand Side can provide useful cooling to the Loop Supply Side. If the setpoints and inlet temperatures are such that heat exchanger could transfer heat from the Loop Supply Side to the Loop Demand Side to meet the cooling setpoint, then the heat exchanger will run. The inlet temperatures must differ by more than the value set in the field called Minimum Temperature Difference to Activate Heat Exchanger for the heat exchanger to operate. If the heat exchanger could undershoot the setpoint, then the flow through the fluid stream connected as the Loop Demand Side will be modulated to just meet the setpoint.
o        Cooling Setpoint On/Off - This control mode is applicable to situations where the Loop Demand Side can provide useful cooling to the Loop Supply Side. If the setpoints and inlet temperatures are such that heat exchanger could transfer heat from the Loop Supply Side to the Loop Demand Side to meet the cooling setpoint, then the heat exchanger will run. The inlet temperatures must differ by more than the value set in the field called Minimum Temperature Difference to Activate Heat Exchanger for the heat exchanger to operate. If it runs, it will run at full capacity and may undershoot the setpoint.
o        Dual Dead band Setpoint Modulated - This control mode is applicable to situations where the Loop Demand Side can provide either useful cooling or heating to the Loop Supply Side. If the setpoints and inlet temperatures are such that heat exchanger could transfer heat from the Loop Demand Side to the Loop Supply Side to meet the lower setpoint, then the heat exchanger will run. If the setpoints and inlet temperatures are such that heat exchanger could transfer heat from the Loop Supply Side to the Loop Demand Side to meet the high setpoint, then the heat exchanger will run. The inlet temperatures must differ by more than the value set in the field called Minimum Temperature Difference to Activate Heat Exchanger for the heat exchanger to operate. If the heat exchanger could overshoot the lower setpoint, or undershoot the higher setpoint, then the flow through the fluid stream connected as the Loop Demand Side will be modulated to just meet the deadband setpoint.
o        Dual Dead band Setpoint On/Off - This control mode is applicable to situations where the Loop Demand Side can provide either useful cooling or heating to the Loop Supply Side. If the setpoints and inlet temperatures are such that heat exchanger could transfer heat from the Loop Demand Side to the Loop Supply Side to meet the lower setpoint, then the heat exchanger will run. If the setpoints and inlet temperatures are such that heat exchanger could transfer heat from the Loop Supply Side to the Loop Demand Side to meet the high setpoint, then the heat exchanger will run. The inlet temperatures must differ by more than the value set in the field called Minimum Temperature Difference to Activate Heat Exchanger for the heat exchanger to operate. If the heat exchanger runs, it will run at full capacity and may overshoot the lower setpoint or undershoot the higher setpoint.
o        Waterside Economizer based on Differential Temperature - This control mode is applicable to situations where the Loop Demand Side can provide useful cooling to the Loop Supply Side. This mode is similar to Cooling Setpoint On/Off except that it ignores any cooling set point and its control is based only on the temperature difference between Loop Demand Side and the Loop Supply Side. The inlet temperatures must differ by more than the value set in the field called Minimum Temperature Difference to Activate Heat Exchanger for the heat exchanger to operate.
o        Waterside Economizer Integrated with Chiller - This control mode is applicable to situations where the heat exchanger operation is integrated with the operation of a specific chiller. Typically the heat exchanger and chiller are in parallel. When conditions are favorable for the heat exchanger to provide cooling to the Loop Supply Side, the heat exchanger is run and the integrated chiller is turned off. When conditions are not favorable, the heat exchanger is completely off and the chiller is allowed to run as usual. If it runs it will run at full capacity and may undershoot the setpoint. The chiller that is integrated with the heat exchanger is identified by entering the name of the chiller. The setpoint and control signal temperatures must differ by more than the value set in the field called Minimum Temperature Difference to Activate Heat Exchanger for the heat exchanger to operate.
 
 
Sizing Factor
Default Value: 1.0
Min & Max: 1– no maximum
Typical Range: 1.15 to 1.25
Units: N/A
 
Description: This input field over sizes the heat exchanger to handle any condition.
 
 
 
District Cooling
Centralized source of chilled water, such as a district cooling system.
 
 
 
Nominal Capacity
Default Value: Autosized
Min & Max: 1– no maximum
Typical Range: N/A
Units: W, kW, tons, Btuh, Mbh
 
Description: This numeric field contains the nominal demand that the district cooling will meet. This field is autosizable.
 
 
 
Capacity Fraction Schedule Name
Default Value: Available 100%
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: This input field contains the name of a schedule that describes how the nominal capacity varies over time. The capacity at a given point in time is determined by the product of the previous field and the value in this schedule.
 
 
 
 
 
District Heating
Centralized source of hot water, such as a district heating system.
 
Nominal Capacity
Default Value: Autosized
Min & Max: 1– no maximum
Typical Range: N/A
Units: W, kW, tons, Btuh, Mbh
 
Description: This numeric field contains the nominal demand that the district heating will meet. This field is autosizable.
 
 
 
Nominal Capacity Modifier
Default Value: Available 100%
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: This input field contains the name of a schedule from the Utilization / Multipliers category in the library. It describes how the nominal capacity varies over time. The capacity at a given point in time is determined by the product of the previous field and the value in this schedule.
 
 
 
Controls
Control strategies allow for the equipment to follow certain setpoint temperatures.
 
Schedule
Description: This control type allows you to enter in a setpoint temperature either as a constant or through a pre-created schedule.
 
Setpoint Type
Default Value: Constant
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: The choices for this input are either “Variable” or “Constant”. Variable allows to a variation in controlling temperatures throughout the day whereas constant is a fixed temperature throughout the day.
 
Input Considerations: N/A
 
 
Control Setpoint
Default Value: Cooling: 44°F (6°C); Heating: 180°F (82°C); Condenser: 85°F (30°C)
Min & Max: 0–999°F
Typical Range: 40–180°F
Units: °F, °C
 
Description: This is the setpoint temperature to which the equipment is controlling to. This may be similar or same as the design leaving temperature
 
Input Considerations: Make sure the design leaving temperature is representative of this temperature.
 
 
Schedule
Default Value: First schedule in list
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Schedules allow you to define 24-hour percentage profiles. Here a schedule can be applied to determine at what specific hours a piece of equipment needs to meet a certain setpoint condition. This field is only available when “Variable” is selected for the set point type.
 
Input Considerations: N/A
 
 
Water Reset Based on OA
Description: The Outdoor Air Reset Setpoint Manager sets the supplied water temperature according to the outdoor air temperature using a reset rule.
 
The reset rule is determined by 2 points:
o            the water setpoint temperature at the outdoor high temperature (SATOH) and
o            the water setpoint temperature at the outdoor low temperature (SATOL).
If the outdoor temperature is above the outdoor high temperature, the water temperature is set to SATOH. If the outdoor temperature is below the outdoor low temperature, the water temperature is set to SATOL. If the outdoor temperature is between the outdoor high and outdoor low temperatures, the water temperature is linearly interpolated between SATOH and SATOL.
 
Schedule
Default Value: First schedule in list
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Schedules allow you to define 24-hour percentage profiles. Here a schedule can be applied to determine at what specific hours a piece of equipment needs to meet a certain setpoint condition and when the temperature is reset based on the OA condition.
 
Input Considerations: N/A
 
 
 
Follow OA Temperature
Description: This controller is used to place a temperature setpoint that is derived from the current outdoor air environmental conditions. The outdoor air conditions are obtained from the weather information during the simulation.
 
Reference Temperature Type
Default Value: Outdoor Air Wet Bulb
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: The reference temperature type is the type of temperature value that the supplied water temperature will follow. The choice is either Outdoor Air Dry Bulb or Outdoor Air Wet Bulb.
 
Input Considerations: N/A
 
 
Offset Temperature Difference
Default Value: 10°F
Min & Max: -999 to 999
Typical Range: 0 to 10
Units: °F, °C
 
Description: This field provides a temperature offset that will be applied to the value of the reference temperature (outdoor air wetbulb/drybulb). If this value is zero, and the limits are met, then the resulting setpoint will be exactly the same as the outdoor air wetbulb/drybulb temperature.
 
Input Considerations: The sign convention is that a positive value here will increase the resulting setpoint to higher than the outdoor air wetbulb/drybulb.
 
 
Maximum Setpoint Temperature
Default Value: Cooling: 54°F (12°C), Condenser: 95°F (35°C), Heating: 180°F (82°C)
Min & Max: -999 to 999
Typical Range: 50 to 200
Units: °F, °C
 
Description: This field provides an upper limit to the setpoint condition.
 
Input Considerations: N/A
 
 
Minimum Setpoint Temperature
Default Value: Cooling: 44°F (6.6°C), Condenser: 55°F (13°C), Heating: 120°F (49°C)
Min & Max: -999 to 999
Typical Range: 20 to 120
Units: °F, °C
 
Description: This field provides a lower limit to the setpoint condition.
 
Input Considerations: N/A
 
 
Dual Setpoint
Description: This controller will allow for two setpoint conditions in the loop – high and low. The temperature of the water loop will float in between these values and either a boiler or cooling tower will be used to maintain the set points at their respective conditions.
 
Setpoint Type
Default Value: Constant
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: The choices for this input are either “Variable” or “Constant”. Variable allows to a variation in controlling temperatures throughout the day whereas constant is a fixed temperature throughout the day.
 
High Setpoint
Default Value: 90°F
Min & Max: -999 to 999
Typical Range: 60 to 100
Units: °F, °C
 
Description: This field provides a higher limit to the setpoint condition. This is only available when the setpoint type is selected as “Constant”.
 
Input Considerations: N/A
 
 
Low Setpoint
Default Value: 60°F
Min & Max: -999 to 999
Typical Range: 20 to 100
Units: °F, °C
 
Description: This field provides a lower limit to the setpoint condition. This is only available when the setpoint type is selected as “Constant”.
 
Input Considerations: N/A
 
 
High Setpoint Schedule
Default Value: First schedule in list
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Schedules allow you to define 24-hour percentage profiles. Here a schedule can be applied to determine at what specific hours a piece of equipment needs to meet the high set point water temperature condition.
 
Input Considerations: N/A
 
 
 
Low Setpoint Schedule
Default Value: First schedule in list
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Schedules allow you to define 24-hour percentage profiles. Here a schedule can be applied to determine at what specific hours a piece of equipment needs to meet the low set point water temperature condition.
 
Input Considerations: N/A
 
 
 
Follow Ground Temperature
Description: This controller is used to place a temperature setpoint that is derived from a current ground temperature. Vertical bore heat exchangers and horizontal bore heat exchanger use deep ground temperature (Site Temperature at Depth). Pond heat exchanger uses shallow depth ground temperatures (Shallow Site Temperature).
 
 
Offset Temperature Difference
Default Value: 10°F
Min & Max: -999 to 999
Typical Range: 20 to 100
Units: °F, °C
 
Description: This field provides a temperature offset that will be applied to the value of the reference ground temperature. If this value is zero, and the limits are met, then the resulting setpoint will be exactly the same as the ground temperature.
 
Input Considerations: The sign convention is that a positive value here will increase the resulting setpoint to higher than the ground temperature.
 
 
Maximum Setpoint Temperature
Default Value: Cooling: 54°F (12°C), Condenser: 95°F (35°C), Heating: 180°F (82°C)
Min & Max: -999 to 999
Typical Range: 60 to 200
Units: °F, °C
 
Description: This field provides an upper limit to the setpoint condition.
 
Input Considerations: N/A
 
 
Minimum Setpoint Temperature
Default Value: Cooling: 44°F (6.6°C), Condenser: 55°F (13°C), Heating: 120°F (49°C)
Min & Max: -999 to 999
Typical Range: 20 to 100
Units: °F, °C
 
Description: This field provides a lower limit to the setpoint condition.
 
Input Considerations: N/A
 
 
 
Optimized Tower
Description: The optimized cooling tower control for water-cooled chillers resets the leaving tower water temperature (the condenser water loop temperature entering the building) to minimize the sum of chiller plus tower energy each hour. Without optimization controls (fixed setpoint), the cooling tower will attempt to reach the setpoint condition, if possible, because the compressor is more efficient at lower condenser operating temperatures. However, there is a trade-off since lowering the tower leaving temperature normally increases the tower energy consumption (unless the tower is also given a more efficient unloading curve). The chiller-tower optimizing algorithm balances the trade-off so the net energy (chiller plus tower) is less than the non-optimized solution. In optimized mode, the tower leaving temperature need not be reset to its lowest design setting, and will often be higher than the un-optimized tower control. The optimum tower leaving temperature is calculated to minimize the total energy consumption of the cooling tower and chiller, using rated tower, performance data, rated chiller performance data, the hourly load, and the outdoor air wet bulb temperature that hour. Note: For water-cooled chillers, optimization is only supported for centrifugal, helical rotary and screw compressor types.
 
Condenser Entering Water Temperature
Default Value: 85°F
Min & Max: 0 to 999
Typical Range: 70 to 95
Units: °F, °C
 
Description: This numeric input field is for the design condenser entering water temperature into the chiller.
 
 
Use System Defaults
Default Value: Yes
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: This input field determines use of system related defaults for minimum lift, maximum condenser entering water temperature, and cooling tower design inlet air wet-bulb temperature.
 
Minimum Lift
Default Value: 54°F
Min & Max: 0 to 999
Typical Range: 30 to 60
Units: °F, °C
 
Description: This field establishes the minimum Lift allowed. Lift is generally thought of as the difference between condenser refrigerant pressure and the evaporator refrigerant pressure. Using defined pressure and temperature relationships, lift also can be related to the difference between the leaving chilled water and the leaving condenser water temperature. Further, when the leaving condenser water temperature and condenser water flow are constant, the entering condenser temperature can be used as a proxy for lift. Because most condenser water systems are designed for constant flow, entering condenser temperature is generally the most common metric for lift, as is implied previously. If the calculated Condenser Entering Water Setpoint falls below (TEvapLvgWater + MinimumLift), then the Condenser Entering Water Setpoint is reset to equal TEvapLvgWater + MinimumLift.
 
 
Maximum Condenser Entering Water Temperature
Default Value: 90°F
Min & Max: 0 to 999
Typical Range: 80 to 100
Units: °F, °C
 
Description: This field establishes the maximum condenser entering water set point temperature allowed. If the scheduled or calculated setpoint is above Condenser Entering Temperature Maximum, then Condenser Entering Temperature Setpoint is reset to equal Condenser Entering Temperature Maximum.
 
 
Cooling Tower Design Inlet Air Wet-Bulb Temperature
Default Value: 78°F
Min & Max: 0 to 999
Typical Range: 60 to 100
Units: °F, °C
 
Description: This field defines the reference wet bulb temperature used to size the cooling tower. Typically, the design condenser entering water temperature equals TwrRefOaWb + TowerApproachTD.
 
 
Follow Return Temperature 
This controller is used to place a temperature set point that is derived from the current loop return temperature. 
 
Return Setpoint Control Type
Default Value: Constant
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: The choices for this input are either “Variable” or “Constant”. Variable allows a variation in controlling temperatures throughout the day whereas constant is a fixed temperature throughout the day.
 
 
Return Variable Control Setpoint
Default Value: Cooling 56°F (13°C); Heating 120°F (49°C)
Min & Max: -999 to 999
Typical Range: 0 to 10
Units: °F, °C
 
Description: A schedule allows you to define variable setpoints. See Temperature Setpoint Schedules for more information on how to create the schedule.
 
 
Maximum Limit Setpoint Temperature
Default Value: Cooling 54°F (12°C); Heating 180°F (82°C)
Min & Max: -999 to 999
Typical Range: 50 to 200
Units: °F, °C
 
Description: This field provides an upper limit to the resulting set point value.
 
 
Minimum Limit Setpoint Temperature
Default Value: Cooling 44°F (6.6°C); Heating 120°F (49°C)
Min & Max: -999 to 999
Typical Range: 20 to 120
Units: °F, °C
 
Description: This field provides a lower limit to the resulting set point value.
 
Availability Manager
An availability manager sets flags telling a plant loop to turn on or off. Each type of availability manager contains a high-level on/off control strategy.
 
High Temperature Turn Off
Description: This strategy is used to turn off a plant loop if a sensed node temperature exceeds a temperature limit.
 
Sensor Location
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: This is the location of the sensor downstream of the equipment listed.
Input Considerations: N/A
 
Temperature
Default Value: Cooling 55°F (12.78°C); Heating 210°F (98.89°C); Condenser 100°F (37.78°C); Mixed 100°F (37.78°C)
Min & Max: -999 to 999
Typical Range: 60 to 200
Units: °F, °C
 
Description: The set point temperature at which the system is turned off.
Input Considerations: N/A
 
 
High Temperature Turn on
Description: This strategy is used to turn on a plant loop if a sensed node temperature exceeds a temperature limit.
 
Sensor Location
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Sets the location of the sensor downstream of the selected equipment.
Input Considerations: N/A
 
 
Temperature
Default Value: Cooling 55°F (12.78°C); Heating 210°F (98.89°C); Condenser 100°F (37.78°C); Mixed 100°F (37.78°C)
Min & Max: -999 to 999
Typical Range: 60 to 200
Units: °F, °C
 
Description: The set point temperature at which the system is turned on.
Input Considerations: N/A
 
 
Low Temperature Turn Off
Description: This strategy is used to turn off a plant loop if a sensed node temperature is below the specified temperature limit.
 
Sensor Location
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Sets the location of the sensor downstream of the selected equipment.
Input Considerations: N/A
 
 
Temperature
Default Value: Cooling 30°F (-1.1°C); Heating 100°F (37.78°C); Condenser 50°F (10°C); Mixed 30°F (-1.1C)
Min & Max: -999 to 999
Typical Range: 32 to 90
Units: °F, °C
 
Description: The set point temperature at which the system is turned off.
Input Considerations: N/A
 
 
Low Temperature Turn on
Description: This strategy is used to turn on a plant loop if a sensed node temperature is below the specified temperature limit.
 
Sensor Location
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: This is the location of the sensor downstream of the equipment listed.
 
Input Considerations: N/A
 
 
Temperature
Default Value: Cooling 30°F (-1.1°C); Heating 100°F (37.78°C); Condenser 50°F (10°C); Mixed 30°F (-1.1C)
Min & Max: -999 to 999
Typical Range: 32 to 90
Units: °F, °C
 
Description: The set point temperature at which the system is turned on.
 
Input Considerations: N/A
 
 
 
 
Sequencing Properties
In this section, there will be two different property areas:
o            Sequencing Properties
o       Schedules (which includes the calendar)
The calendar will be a tool for you to select which days will have a specific hourly schedule for sequencing. The calendar by default will have all of the days covered with the same hourly schedule. This tool will also have a legend where you can select an hourly schedule and apply it to a certain day type.
 
Load Distribution Control
Default Value: Sequential
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: The Load Distribution Scheme selects the algorithm used to sequence equipment operation in order to meet the loop demand. Currently, there are five schemes.
  • Optimal operates each piece of equipment at its optimal part load ratio and will operate the last component between its minimum and maximum part load ratio in order to meet the loop demand.
  • Sequential Load loads each piece of equipment sequentially in the order specified in the loop to its maximum part load ratio and will operate the last required piece of equipment between its minimum and maximum part load ratio in order to meet the loop demand.
  • Uniform Load evenly distributes the loop demand among all available components in the loop for a given load range.
  • Sequential Uniform PLR loads all equipment in the plant to a uniform part load ratio (PLR). Components are loaded sequentially based on the order specified in the plant until each component is fully loaded, at which point the next subsequent component is added and the load is distributed uniformly based on part load ratio (PLR) between the components.
  • Uniform PLR will load all equipment on the plant list to a uniform part load ratio (PLR). No equipment will be loaded below its minimum PLR. If the total load is less than the sum of all equipment in the loop operating at their respective minimum PLRs, then the last item in the equipment list is dropped and the load is distributed based on a uniform PLR for the remaining plant equipment.
 
Input Consideration: N/A
 
 
Name
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Enter in the name of the plant sequence.
 
 
Scheme
 
Default Value: Equipment to Max Capacity
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: In this dropdown, there will be a set of schemes that you can select for each sequence created.
 
The schemes are as follows:
Equipment to Max Capacity
By Outdoor Dry Bulb
By Outdoor Dew Point
By Outdoor Wet Bulb Difference
By Load, Equipment Set Point
By Outdoor Wet Bulb
By Outdoor Dry Bulb Difference
By Outdoor Dew Point Difference
 
 
 
 
Equipment to Max Capacity
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: As the loop runs, the equipment will also run as specified (until its capacity is maxed out), unless turned off by the loop flow resolver to maintain continuity in the fluid loop. By default, if no sequencing is added, this is the sequence used.
 
 
By Load
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Each equipment series added has a low and high limit of load associated. If the demand is lower than the low limit, the equipment will not turn on, if the demand is higher than the load specified, this sequence will not run. You can set equipment load sequences per equipment or equipment series. By default, the load sequence will have all equipment within one load range, you will have to delete equipment if you want it to appear in another equipment series.
 
 
By Leaving Setpoint
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Each component controlled under temperature based control will have its own setpoint different from the loop setpoint. This scheme is common to many present-day Energy Management Systems sequencing. In this scheme, the sequencing is done based on the order specified in the control object described below. All you need to do is set the order of the setpoints to be met.
 
 
 
By Outdoor Dry Bulb, By Outdoor Wetbulb, By Outdoor Relative Humidity, By Outdoor Dew Point
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Similar to the load scheme, the outdoor operation sequences define the different ranges of the various environmental parameters and which equipment list is valid for each range. If the parameter is lower than the low limit, the equipment will not turn on, if the outside air condition is higher than the parameter listed, this sequence will not run. You can set equipment load sequences per equipment or equipment series.
 
 
By Outdoor Dry Bulb Difference, By Outdoor Wet Bulb Difference
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Similar to the load scheme, the delta temperature based control strategies help to control any condenser equipment based on the difference between the leaving condition of the equipment and any environmental temperature. For example a cooling tower can be controlled by a strategy, which looks at the difference between the tower inlet temperature and wet-bulb temperature. A difference range is specified for each equipment list.
 
 
 
 
Demand Load Properties
 
This is where you can add loads that are considered demand loads. The load can be used to impose a base load on the cooling or heating equipment. The add button will continue to add new loads into the loop. Loads can also be copied and deleted as well.
 
Here are the field names of the demand load.
 
Name
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Enter in the name of the demand load.
 
Input Considerations: N/A
 
AutoSize Demand Load
 
The demand load can be determined by the software based on the constraints of the calulation. Otherwise manual specifications can be made as outlined below.
 
Max Load
Default Value: 0
Min & Max: -999999 to 999999
Typical Range: N/A
Units: Tons, kW, W
 
Description: This is the maximum load the loop will have to address.
 
Input Considerations: N/A
 
 
Max Flow Rate
Default Value: 0
Min & Max: 0 to 999999
Typical Range: N/A
Units: gmp, L/s
 
Description: This is the flow rate for the demand load. When the flow rate and load are entered, a temperature delta is determined.
 
Input Considerations: N/A
 
Schedule
Default Value: N/A
Min & Max: N/A
Typical Range: N/A
Units: N/A
 
Description: Schedules allow you to define 24-hour percentage profiles. Here a schedule can be applied to determine at what specific hours a varying amount of load is on a loop. This will change the demand on the associated equipment in that loop.
 
Input Considerations: N/A