This group of objects consists of tabular data which are
used to characterize the performance of HVAC equipment. The
use of performance tables eliminate the need to perform a
regression analysis to calculate the performance curve
equation coefficients. The following descriptions define the
input requirements for the performance table objects.
Input for tables representing data with one or more
independent variables.
A unique user-assigned name for an instance of a lookup
table. When a table is used, it is referenced by this name.
The name of this table object may be used anywhere a valid
performance curve object is allowed.
Field:
Independent Variable List Name[LINK]
The name of a Table:IndependentVariableList
object that defines the independent variables that comprise
the dimensions of the tabular data.
Field: Normalization
Method[LINK]
Determines if and how this output will be normalized.
Choices are:
No: Do not normalize output.
DivisorOnly: Normalize the output using only
the value entered into the Normalization Divisor field,
below.
AutomaticWithDivisor: Normalize the output by
dividing the output data by the value of the table at each of
the independent variable normalization reference values in the
associated independent variable list AND dividing by the value
entered into the Normalization Divisor field, below.
Normalization applies to the Output Value fields as well as
the Minimum and Maximum Output fields.
Field: Normalization
Divisor[LINK]
Defines a value by which output values are normalized if
the Normalization Method field is set to DivisorOnly
or AutomaticWithDivisor. Default is 1.0.
Field: Minimum Output[LINK]
The (non-normalized) minimum allowable value of the
evaluated table after interpolation and extrapolation. Values
less than the minimum will be replaced by the minimum. If this
field is left blank, no limit is imposed.
Field: Maximum Output[LINK]
The (non-normalized) maximum allowable value of the
evaluated table after interpolation and extrapolation. Values
greater than the maximum will be replaced by the maximum. If
this field is left blank, no limit is imposed.
Field: Output Unit Type[LINK]
This field is used to indicate the kind of units that may
be associated with the output values. It is used by interfaces
or input editors (e.g., IDF Editor) to display the appropriate
SI and IP units for the Minimum Output and Maximum Output. If
none of these options are appropriate, select
Dimensionless which will have no unit conversion.
Options are:
Dimensionless
Capacity
Power
Field: External File
Name[LINK]
The name of an external CSV file that represents the
tabular data. This file should be formatted such that the data
for this particular output is ordered according to the order
of the corresponding independent variables. For example, for
three independent variables (iv1,
iv2, iv3) with 3, 2, and 4 values
respectively. The output values
(out[iv1][iv2][iv3]) should be ordered as:
iv1 |
iv2 |
iv3 |
output |
iv1[1] |
iv2[1] |
iv3[1] |
out[1][1][1] |
iv1[1] |
iv2[1] |
iv3[2] |
out[1][1][2] |
iv1[1] |
iv2[1] |
iv3[3] |
out[1][1][3] |
iv1[1] |
iv2[1] |
iv3[4] |
out[1][1][4] |
iv1[1] |
iv2[2] |
iv3[1] |
out[1][2][1] |
iv1[1] |
iv2[2] |
iv3[2] |
out[1][2][2] |
iv1[1] |
iv2[2] |
iv3[3] |
out[1][2][3] |
iv1[1] |
iv2[2] |
iv3[4] |
out[1][2][4] |
iv1[2] |
iv2[1] |
iv3[1] |
out[2][1][1] |
iv1[2] |
iv2[1] |
iv3[2] |
out[2][1][2] |
iv1[2] |
iv2[1] |
iv3[3] |
out[2][1][3] |
iv1[2] |
iv2[1] |
iv3[4] |
out[2][1][4] |
iv1[2] |
iv2[2] |
iv3[1] |
out[2][2][1] |
iv1[2] |
iv2[2] |
iv3[2] |
out[2][2][2] |
iv1[2] |
iv2[2] |
iv3[3] |
out[2][2][3] |
iv1[2] |
iv2[2] |
iv3[4] |
out[2][2][4] |
iv1[3] |
iv2[1] |
iv3[1] |
out[3][1][1] |
iv1[3] |
iv2[1] |
iv3[2] |
out[3][1][2] |
iv1[3] |
iv2[1] |
iv3[3] |
out[3][1][3] |
iv1[3] |
iv2[1] |
iv3[4] |
out[3][1][4] |
iv1[3] |
iv2[2] |
iv3[1] |
out[3][2][1] |
iv1[3] |
iv2[2] |
iv3[2] |
out[3][2][2] |
iv1[3] |
iv2[2] |
iv3[3] |
out[3][2][3] |
iv1[3] |
iv2[2] |
iv3[4] |
out[3][2][4] |
Alternatively, the output may be defined using the
Output Value <x> fields below.
Field: External
File Column Number[LINK]
The column number (starting at 1) in the CSV file
corresponding to this output.
Field:
External File Starting Row Number[LINK]
The row number (starting at 1) in the CSV file where the
data for this output begins. If there are not enough rows of
data to fill out the full grid of data an error will be
presented to the user.
Output Value <x>[LINK]
If not reading from an external file, this field is
repeated to capture the full set of output data in the table
(if not otherwise defined in an external file). The data for
this particular output is ordered according to the order of
the corresponding independent variables. For example, for
three independent variables (iv1,
iv2, iv3) with 3, 2, and 4 values
respectively. The output values
(out[iv1][iv2][iv3]) should be ordered as:
iv1 |
iv2 |
iv3 |
output |
iv1[1] |
iv2[1] |
iv3[1] |
out[1][1][1] |
iv1[1] |
iv2[1] |
iv3[2] |
out[1][1][2] |
iv1[1] |
iv2[1] |
iv3[3] |
out[1][1][3] |
iv1[1] |
iv2[1] |
iv3[4] |
out[1][1][4] |
iv1[1] |
iv2[2] |
iv3[1] |
out[1][2][1] |
iv1[1] |
iv2[2] |
iv3[2] |
out[1][2][2] |
iv1[1] |
iv2[2] |
iv3[3] |
out[1][2][3] |
iv1[1] |
iv2[2] |
iv3[4] |
out[1][2][4] |
iv1[2] |
iv2[1] |
iv3[1] |
out[2][1][1] |
iv1[2] |
iv2[1] |
iv3[2] |
out[2][1][2] |
iv1[2] |
iv2[1] |
iv3[3] |
out[2][1][3] |
iv1[2] |
iv2[1] |
iv3[4] |
out[2][1][4] |
iv1[2] |
iv2[2] |
iv3[1] |
out[2][2][1] |
iv1[2] |
iv2[2] |
iv3[2] |
out[2][2][2] |
iv1[2] |
iv2[2] |
iv3[3] |
out[2][2][3] |
iv1[2] |
iv2[2] |
iv3[4] |
out[2][2][4] |
iv1[3] |
iv2[1] |
iv3[1] |
out[3][1][1] |
iv1[3] |
iv2[1] |
iv3[2] |
out[3][1][2] |
iv1[3] |
iv2[1] |
iv3[3] |
out[3][1][3] |
iv1[3] |
iv2[1] |
iv3[4] |
out[3][1][4] |
iv1[3] |
iv2[2] |
iv3[1] |
out[3][2][1] |
iv1[3] |
iv2[2] |
iv3[2] |
out[3][2][2] |
iv1[3] |
iv2[2] |
iv3[3] |
out[3][2][3] |
iv1[3] |
iv2[2] |
iv3[4] |
out[3][2][4] |
Table:Lookup,
HPACCoolCapFT, !- Name
HPACCoolCapFT_IndependentVariableList, !- Independent Variable List Name
AutomaticWithDivisor, !- Normalization Method
, !- Normalization Divisor
0, !- Minimum Output
40000, !- Maximum Output
Dimensionless, !- Output Unit Type
, !- External File Name
, !- External File Column Number
, !- External File Starting Row Number
24421.69383, 22779.73113, 21147.21662, 19794.00525, 19524.15032, 18178.81244, 16810.36004,
25997.3589, 24352.1562, 22716.4017, 21360.49033, 21090.0954, 19742.05753, 18370.84513,
28392.31868, 26742.74198, 25102.61348, 23743.0571, 23471.93318, 22120.2503, 20745.3119,
29655.22876, 28003.546, 26361.31143, 25000, 24728.52506, 23375.08713, 21998.35468,
31094.97495, 29441.02425, 27796.52175, 26433.32038, 26161.46745, 24806.13958, 23427.47518,
33988.3473, 32330.1846, 30681.4701, 29314.75872, 29042.2038, 27683.36592, 26301.11353;
The current value of the performance table. Performance
curves and tables use the same output variable. This value is
averaged over the time step being reported. Inactive or unused
performance curves will show a value of -999 (e.g., equipment
is off, a specific performance curve is not required for this
aspect of the equipment model at this time step, etc.). This
value means that the performance curve was not called during
the simulation and, therefore, not evaluated. This inactive
state value is only set at the beginning of each environment.
When averaging over long periods of time, this inactive state
value may skew results. In this case, use a detailed reporting
frequency (ref. Output:Variable
object) to view results at each HVAC time step.
Table:IndependentVariableList[LINK]
A list of Table:IndependentVariable
references that define the size and dimensions of the data for
one or more Table:Lookup
objects. The order of this list defines the order that the
tabular data must be defined. The output values in the Table:Lookup
associated with this list will list the output in an order
cycling through the last item in the list first, and then the
second to last, and so on with the the first item cycling
last. For example, for three independent variables
(iv1, iv2, iv3) with 3,
2, and 4 values respectively. The output values
(out[iv1][iv2][iv3]) should be ordered as:
iv1 |
iv2 |
iv3 |
output |
iv1[1] |
iv2[1] |
iv3[1] |
out[1][1][1] |
iv1[1] |
iv2[1] |
iv3[2] |
out[1][1][2] |
iv1[1] |
iv2[1] |
iv3[3] |
out[1][1][3] |
iv1[1] |
iv2[1] |
iv3[4] |
out[1][1][4] |
iv1[1] |
iv2[2] |
iv3[1] |
out[1][2][1] |
iv1[1] |
iv2[2] |
iv3[2] |
out[1][2][2] |
iv1[1] |
iv2[2] |
iv3[3] |
out[1][2][3] |
iv1[1] |
iv2[2] |
iv3[4] |
out[1][2][4] |
iv1[2] |
iv2[1] |
iv3[1] |
out[2][1][1] |
iv1[2] |
iv2[1] |
iv3[2] |
out[2][1][2] |
iv1[2] |
iv2[1] |
iv3[3] |
out[2][1][3] |
iv1[2] |
iv2[1] |
iv3[4] |
out[2][1][4] |
iv1[2] |
iv2[2] |
iv3[1] |
out[2][2][1] |
iv1[2] |
iv2[2] |
iv3[2] |
out[2][2][2] |
iv1[2] |
iv2[2] |
iv3[3] |
out[2][2][3] |
iv1[2] |
iv2[2] |
iv3[4] |
out[2][2][4] |
iv1[3] |
iv2[1] |
iv3[1] |
out[3][1][1] |
iv1[3] |
iv2[1] |
iv3[2] |
out[3][1][2] |
iv1[3] |
iv2[1] |
iv3[3] |
out[3][1][3] |
iv1[3] |
iv2[1] |
iv3[4] |
out[3][1][4] |
iv1[3] |
iv2[2] |
iv3[1] |
out[3][2][1] |
iv1[3] |
iv2[2] |
iv3[2] |
out[3][2][2] |
iv1[3] |
iv2[2] |
iv3[3] |
out[3][2][3] |
iv1[3] |
iv2[2] |
iv3[4] |
out[3][2][4] |
A unique user-assigned name for a list of independent
variables. This name is referenced by Table:Lookup
objects. The name of this list object may be referenced by any
number of Table:Lookup
objects.
Field: Independent
Variable <x> Name[LINK]
This field is repeated for the number of independent
variables that define the dimensions of any corresponding Table:Lookup
objects that refer to this list. Each instance provides the
name of a Table:IndependentVariable
object that defines the values and properties of an
independent variable.
Table:IndependentVariableList,
HPACCoolCapFT_IndependentVariableList, !- Name
HPACCoolCapFT_Tewb, !- Independent Variable 1 Name
HPACCoolCapFT_Todb; !- Independent Variable 2 Name
Table:IndependentVariable[LINK]
Independent variables are used to define the size and
dimensions of a Table:Lookup
object.
A unique user-assigned name for an independent variables.
This name is referenced by Table:IndependentVariableList
objects. The name of this object may be referenced by any
number of Table:IndependentVariableList
objects.
Field: Interpolation
Method[LINK]
Method used to determine the value of the table within the
bounds of its independent variables. The choices are:
Method used to determine the value of the table beyond the
bounds of its independent variables. The choices are:
Constant: Value is the same as the
interpolated value at the closest point along the table’s
boundary.
Linear: Value is linearly extrapolated in all
dimensions from the interpolated value at the closest point
along the table’s boundary.
Field: Minimum Value[LINK]
The minimum allowable value. Table:Lookup
output for values between this value and the lowest value
provided for this independent variable will be extrapolated
according to the extrapolation method. Below this value,
extrapolation is held constant and a warning will be issued.
If extrapolation method is “Unavailable”, the corresponding
equipment will be disabled for all values less than the lowest
independent variable value, regardless of the minimum value
set here.
Field: Maximum Value[LINK]
The maximum allowable value. Table:Lookup
output for values between this value and the highest value
provided for this independent variable will be extrapolated
according to the extrapolation method. Above this value,
extrapolation is held constant and a warning will be issued.
If extrapolation method is “Unavailable”, the corresponding
equipment will be disabled for all values greater than the
highest independent variable value, regardless of the maximum
value set here.
Field:
Normalization Reference Value[LINK]
The value of this independent variable where nominal or
rated output is defined. This will be used to normalize the
data so that the outputs of any Table:Lookup
at this value (and the corresponding Normalization Reference
Values of the other independent variables described in the
same Table:IndependentVariableList
object) are equal to 1.0. If left blank, no normalization will
be calculated. If this field is left blank the Normalization
Reference Value of all other Table:IndependentVariable
objects within the same Table:IndependentVariableList
must also be left blank.
Field: Unit Type[LINK]
This field is used to indicate the kind of units that may
be associated with this independent variable. It is used by
interfaces or input editors (e.g., IDF Editor) to display the
appropriate SI and IP units for the Minimum Value and Maximum
Value. The available options are shown below. If none of these
options are appropriate, select Dimensionless which
will have no unit conversion.
Dimensionless
Temperature
VolumetricFlow
MassFlow
Distance
Power
Field: External File
Name[LINK]
The name of an external CSV file that represents the
tabular data. This file should be formatted such that the data
for any output is ordered according to the order of the
corresponding independent variables. For example, for three
independent variables (iv1, iv2,
iv3) with 3, 2, and 4 values respectively. The
output values (out[iv1][iv2][iv3]) should be
ordered as:
iv1 |
iv2 |
iv3 |
output |
iv1[1] |
iv2[1] |
iv3[1] |
out[1][1][1] |
iv1[1] |
iv2[1] |
iv3[2] |
out[1][1][2] |
iv1[1] |
iv2[1] |
iv3[3] |
out[1][1][3] |
iv1[1] |
iv2[1] |
iv3[4] |
out[1][1][4] |
iv1[1] |
iv2[2] |
iv3[1] |
out[1][2][1] |
iv1[1] |
iv2[2] |
iv3[2] |
out[1][2][2] |
iv1[1] |
iv2[2] |
iv3[3] |
out[1][2][3] |
iv1[1] |
iv2[2] |
iv3[4] |
out[1][2][4] |
iv1[2] |
iv2[1] |
iv3[1] |
out[2][1][1] |
iv1[2] |
iv2[1] |
iv3[2] |
out[2][1][2] |
iv1[2] |
iv2[1] |
iv3[3] |
out[2][1][3] |
iv1[2] |
iv2[1] |
iv3[4] |
out[2][1][4] |
iv1[2] |
iv2[2] |
iv3[1] |
out[2][2][1] |
iv1[2] |
iv2[2] |
iv3[2] |
out[2][2][2] |
iv1[2] |
iv2[2] |
iv3[3] |
out[2][2][3] |
iv1[2] |
iv2[2] |
iv3[4] |
out[2][2][4] |
iv1[3] |
iv2[1] |
iv3[1] |
out[3][1][1] |
iv1[3] |
iv2[1] |
iv3[2] |
out[3][1][2] |
iv1[3] |
iv2[1] |
iv3[3] |
out[3][1][3] |
iv1[3] |
iv2[1] |
iv3[4] |
out[3][1][4] |
iv1[3] |
iv2[2] |
iv3[1] |
out[3][2][1] |
iv1[3] |
iv2[2] |
iv3[2] |
out[3][2][2] |
iv1[3] |
iv2[2] |
iv3[3] |
out[3][2][3] |
iv1[3] |
iv2[2] |
iv3[4] |
out[3][2][4] |
Independent variable values must appear in
ascending order (an error will be issued if
this is not the case).
Alternatively, the independent variables may be defined
using the Value <x> fields below.
Field: External
File Column Number[LINK]
The column number (starting at 1) in the CSV file
corresponding to this independent variable. As the values of
the independent variables each repeat over a defined cycle,
EnergyPlus will only read unique values from this column.
EnergyPlus does not validate that the cycles are repeating
correctly. In fact, the same data can be read by only defining
each value once as it is first encountered:
iv1 |
iv2 |
iv3 |
output |
iv1[1] |
iv2[1] |
iv3[1] |
out[1][1][1] |
|
|
iv3[2] |
out[1][1][2] |
|
|
iv3[3] |
out[1][1][3] |
|
|
iv3[4] |
out[1][1][4] |
|
iv2[2] |
|
out[1][2][1] |
|
|
|
out[1][2][2] |
|
|
|
out[1][2][3] |
|
|
|
out[1][2][4] |
iv1[2] |
|
|
out[2][1][1] |
|
|
|
out[2][1][2] |
|
|
|
out[2][1][3] |
|
|
|
out[2][1][4] |
|
|
|
out[2][2][1] |
|
|
|
out[2][2][2] |
|
|
|
out[2][2][3] |
|
|
|
out[2][2][4] |
iv1[3] |
|
|
out[3][1][1] |
|
|
|
out[3][1][2] |
|
|
|
out[3][1][3] |
|
|
|
out[3][1][4] |
|
|
|
out[3][2][1] |
|
|
|
out[3][2][2] |
|
|
|
out[3][2][3] |
|
|
|
out[3][2][4] |
Field:
External File Starting Row Number[LINK]
The row number (starting at 1) in the CSV file where the
data for this independent variable begins. Any values in the
same column below this row are considered part of the
range.
Field: Value <x>[LINK]
If not reading from an external file, this field is
repeated to capture the full set of values for this
independent variable. These values must be defined in
ascending order (an error will be issued if
this is not the case).
Table:IndependentVariable,
HPACCoolCapFT_Tewb, !- Name
Cubic, !- Interpolation Method
Constant, !- Extrapolation Method
12.77778, !- Minimum Value
23.88889, !- Maximum Value
19.44449, !- Normalization Reference Value
Temperature, !- Unit Type
, !- External File Name
, !- External File Column Number
, !- External File Starting Row Number
12.77778, !- Value 1
15.00000, !- Value 2
18.00000, !- Value 3
19.44449, !- Value 4
21.00000, !- Value 5
23.88889; !- Value 6
Group Performance Tables[LINK]
This group of objects consists of tabular data which are used to characterize the performance of HVAC equipment. The use of performance tables eliminate the need to perform a regression analysis to calculate the performance curve equation coefficients. The following descriptions define the input requirements for the performance table objects.
Table:Lookup[LINK]
Input for tables representing data with one or more independent variables.
Inputs[LINK]
Field: Name[LINK]
A unique user-assigned name for an instance of a lookup table. When a table is used, it is referenced by this name. The name of this table object may be used anywhere a valid performance curve object is allowed.
Field: Independent Variable List Name[LINK]
The name of a Table:IndependentVariableList object that defines the independent variables that comprise the dimensions of the tabular data.
Field: Normalization Method[LINK]
Determines if and how this output will be normalized. Choices are:
No: Do not normalize output.
DivisorOnly: Normalize the output using only the value entered into the Normalization Divisor field, below.
AutomaticWithDivisor: Normalize the output by dividing the output data by the value of the table at each of the independent variable normalization reference values in the associated independent variable list AND dividing by the value entered into the Normalization Divisor field, below.
Normalization applies to the Output Value fields as well as the Minimum and Maximum Output fields.
Field: Normalization Divisor[LINK]
Defines a value by which output values are normalized if the Normalization Method field is set to DivisorOnly or AutomaticWithDivisor. Default is 1.0.
Field: Minimum Output[LINK]
The (non-normalized) minimum allowable value of the evaluated table after interpolation and extrapolation. Values less than the minimum will be replaced by the minimum. If this field is left blank, no limit is imposed.
Field: Maximum Output[LINK]
The (non-normalized) maximum allowable value of the evaluated table after interpolation and extrapolation. Values greater than the maximum will be replaced by the maximum. If this field is left blank, no limit is imposed.
Field: Output Unit Type[LINK]
This field is used to indicate the kind of units that may be associated with the output values. It is used by interfaces or input editors (e.g., IDF Editor) to display the appropriate SI and IP units for the Minimum Output and Maximum Output. If none of these options are appropriate, select Dimensionless which will have no unit conversion. Options are:
Dimensionless
Capacity
Power
Field: External File Name[LINK]
The name of an external CSV file that represents the tabular data. This file should be formatted such that the data for this particular output is ordered according to the order of the corresponding independent variables. For example, for three independent variables (
iv1,iv2,iv3) with 3, 2, and 4 values respectively. The output values (out[iv1][iv2][iv3]) should be ordered as:iv1iv2iv3outputiv1[1]iv2[1]iv3[1]out[1][1][1]iv1[1]iv2[1]iv3[2]out[1][1][2]iv1[1]iv2[1]iv3[3]out[1][1][3]iv1[1]iv2[1]iv3[4]out[1][1][4]iv1[1]iv2[2]iv3[1]out[1][2][1]iv1[1]iv2[2]iv3[2]out[1][2][2]iv1[1]iv2[2]iv3[3]out[1][2][3]iv1[1]iv2[2]iv3[4]out[1][2][4]iv1[2]iv2[1]iv3[1]out[2][1][1]iv1[2]iv2[1]iv3[2]out[2][1][2]iv1[2]iv2[1]iv3[3]out[2][1][3]iv1[2]iv2[1]iv3[4]out[2][1][4]iv1[2]iv2[2]iv3[1]out[2][2][1]iv1[2]iv2[2]iv3[2]out[2][2][2]iv1[2]iv2[2]iv3[3]out[2][2][3]iv1[2]iv2[2]iv3[4]out[2][2][4]iv1[3]iv2[1]iv3[1]out[3][1][1]iv1[3]iv2[1]iv3[2]out[3][1][2]iv1[3]iv2[1]iv3[3]out[3][1][3]iv1[3]iv2[1]iv3[4]out[3][1][4]iv1[3]iv2[2]iv3[1]out[3][2][1]iv1[3]iv2[2]iv3[2]out[3][2][2]iv1[3]iv2[2]iv3[3]out[3][2][3]iv1[3]iv2[2]iv3[4]out[3][2][4]Alternatively, the output may be defined using the Output Value <x> fields below.
Field: External File Column Number[LINK]
The column number (starting at 1) in the CSV file corresponding to this output.
Field: External File Starting Row Number[LINK]
The row number (starting at 1) in the CSV file where the data for this output begins. If there are not enough rows of data to fill out the full grid of data an error will be presented to the user.
Output Value <x>[LINK]
If not reading from an external file, this field is repeated to capture the full set of output data in the table (if not otherwise defined in an external file). The data for this particular output is ordered according to the order of the corresponding independent variables. For example, for three independent variables (
iv1,iv2,iv3) with 3, 2, and 4 values respectively. The output values (out[iv1][iv2][iv3]) should be ordered as:iv1iv2iv3outputiv1[1]iv2[1]iv3[1]out[1][1][1]iv1[1]iv2[1]iv3[2]out[1][1][2]iv1[1]iv2[1]iv3[3]out[1][1][3]iv1[1]iv2[1]iv3[4]out[1][1][4]iv1[1]iv2[2]iv3[1]out[1][2][1]iv1[1]iv2[2]iv3[2]out[1][2][2]iv1[1]iv2[2]iv3[3]out[1][2][3]iv1[1]iv2[2]iv3[4]out[1][2][4]iv1[2]iv2[1]iv3[1]out[2][1][1]iv1[2]iv2[1]iv3[2]out[2][1][2]iv1[2]iv2[1]iv3[3]out[2][1][3]iv1[2]iv2[1]iv3[4]out[2][1][4]iv1[2]iv2[2]iv3[1]out[2][2][1]iv1[2]iv2[2]iv3[2]out[2][2][2]iv1[2]iv2[2]iv3[3]out[2][2][3]iv1[2]iv2[2]iv3[4]out[2][2][4]iv1[3]iv2[1]iv3[1]out[3][1][1]iv1[3]iv2[1]iv3[2]out[3][1][2]iv1[3]iv2[1]iv3[3]out[3][1][3]iv1[3]iv2[1]iv3[4]out[3][1][4]iv1[3]iv2[2]iv3[1]out[3][2][1]iv1[3]iv2[2]iv3[2]out[3][2][2]iv1[3]iv2[2]iv3[3]out[3][2][3]iv1[3]iv2[2]iv3[4]out[3][2][4]Example IDF[LINK]
Outputs[LINK]
Performance Curve Output Value [][LINK]
The current value of the performance table. Performance curves and tables use the same output variable. This value is averaged over the time step being reported. Inactive or unused performance curves will show a value of -999 (e.g., equipment is off, a specific performance curve is not required for this aspect of the equipment model at this time step, etc.). This value means that the performance curve was not called during the simulation and, therefore, not evaluated. This inactive state value is only set at the beginning of each environment. When averaging over long periods of time, this inactive state value may skew results. In this case, use a detailed reporting frequency (ref. Output:Variable object) to view results at each HVAC time step.
Performance Curve Input Variable <x> Value [][LINK]
Table:IndependentVariableList[LINK]
A list of Table:IndependentVariable references that define the size and dimensions of the data for one or more Table:Lookup objects. The order of this list defines the order that the tabular data must be defined. The output values in the Table:Lookup associated with this list will list the output in an order cycling through the last item in the list first, and then the second to last, and so on with the the first item cycling last. For example, for three independent variables (
iv1,iv2,iv3) with 3, 2, and 4 values respectively. The output values (out[iv1][iv2][iv3]) should be ordered as:iv1iv2iv3outputiv1[1]iv2[1]iv3[1]out[1][1][1]iv1[1]iv2[1]iv3[2]out[1][1][2]iv1[1]iv2[1]iv3[3]out[1][1][3]iv1[1]iv2[1]iv3[4]out[1][1][4]iv1[1]iv2[2]iv3[1]out[1][2][1]iv1[1]iv2[2]iv3[2]out[1][2][2]iv1[1]iv2[2]iv3[3]out[1][2][3]iv1[1]iv2[2]iv3[4]out[1][2][4]iv1[2]iv2[1]iv3[1]out[2][1][1]iv1[2]iv2[1]iv3[2]out[2][1][2]iv1[2]iv2[1]iv3[3]out[2][1][3]iv1[2]iv2[1]iv3[4]out[2][1][4]iv1[2]iv2[2]iv3[1]out[2][2][1]iv1[2]iv2[2]iv3[2]out[2][2][2]iv1[2]iv2[2]iv3[3]out[2][2][3]iv1[2]iv2[2]iv3[4]out[2][2][4]iv1[3]iv2[1]iv3[1]out[3][1][1]iv1[3]iv2[1]iv3[2]out[3][1][2]iv1[3]iv2[1]iv3[3]out[3][1][3]iv1[3]iv2[1]iv3[4]out[3][1][4]iv1[3]iv2[2]iv3[1]out[3][2][1]iv1[3]iv2[2]iv3[2]out[3][2][2]iv1[3]iv2[2]iv3[3]out[3][2][3]iv1[3]iv2[2]iv3[4]out[3][2][4]Inputs[LINK]
Field: Name[LINK]
A unique user-assigned name for a list of independent variables. This name is referenced by Table:Lookup objects. The name of this list object may be referenced by any number of Table:Lookup objects.
Field: Independent Variable <x> Name[LINK]
This field is repeated for the number of independent variables that define the dimensions of any corresponding Table:Lookup objects that refer to this list. Each instance provides the name of a Table:IndependentVariable object that defines the values and properties of an independent variable.
Example IDF[LINK]
Table:IndependentVariable[LINK]
Independent variables are used to define the size and dimensions of a Table:Lookup object.
Inputs[LINK]
Field: Name[LINK]
A unique user-assigned name for an independent variables. This name is referenced by Table:IndependentVariableList objects. The name of this object may be referenced by any number of Table:IndependentVariableList objects.
Field: Interpolation Method[LINK]
Method used to determine the value of the table within the bounds of its independent variables. The choices are:
Linear
Cubic
Field: Extrapolation Method[LINK]
Method used to determine the value of the table beyond the bounds of its independent variables. The choices are:
Constant: Value is the same as the interpolated value at the closest point along the table’s boundary.
Linear: Value is linearly extrapolated in all dimensions from the interpolated value at the closest point along the table’s boundary.
Field: Minimum Value[LINK]
The minimum allowable value. Table:Lookup output for values between this value and the lowest value provided for this independent variable will be extrapolated according to the extrapolation method. Below this value, extrapolation is held constant and a warning will be issued. If extrapolation method is “Unavailable”, the corresponding equipment will be disabled for all values less than the lowest independent variable value, regardless of the minimum value set here.
Field: Maximum Value[LINK]
The maximum allowable value. Table:Lookup output for values between this value and the highest value provided for this independent variable will be extrapolated according to the extrapolation method. Above this value, extrapolation is held constant and a warning will be issued. If extrapolation method is “Unavailable”, the corresponding equipment will be disabled for all values greater than the highest independent variable value, regardless of the maximum value set here.
Field: Normalization Reference Value[LINK]
The value of this independent variable where nominal or rated output is defined. This will be used to normalize the data so that the outputs of any Table:Lookup at this value (and the corresponding Normalization Reference Values of the other independent variables described in the same Table:IndependentVariableList object) are equal to 1.0. If left blank, no normalization will be calculated. If this field is left blank the Normalization Reference Value of all other Table:IndependentVariable objects within the same Table:IndependentVariableList must also be left blank.
Field: Unit Type[LINK]
This field is used to indicate the kind of units that may be associated with this independent variable. It is used by interfaces or input editors (e.g., IDF Editor) to display the appropriate SI and IP units for the Minimum Value and Maximum Value. The available options are shown below. If none of these options are appropriate, select Dimensionless which will have no unit conversion.
Dimensionless
Temperature
VolumetricFlow
MassFlow
Distance
Power
Field: External File Name[LINK]
The name of an external CSV file that represents the tabular data. This file should be formatted such that the data for any output is ordered according to the order of the corresponding independent variables. For example, for three independent variables (
iv1,iv2,iv3) with 3, 2, and 4 values respectively. The output values (out[iv1][iv2][iv3]) should be ordered as:iv1iv2iv3outputiv1[1]iv2[1]iv3[1]out[1][1][1]iv1[1]iv2[1]iv3[2]out[1][1][2]iv1[1]iv2[1]iv3[3]out[1][1][3]iv1[1]iv2[1]iv3[4]out[1][1][4]iv1[1]iv2[2]iv3[1]out[1][2][1]iv1[1]iv2[2]iv3[2]out[1][2][2]iv1[1]iv2[2]iv3[3]out[1][2][3]iv1[1]iv2[2]iv3[4]out[1][2][4]iv1[2]iv2[1]iv3[1]out[2][1][1]iv1[2]iv2[1]iv3[2]out[2][1][2]iv1[2]iv2[1]iv3[3]out[2][1][3]iv1[2]iv2[1]iv3[4]out[2][1][4]iv1[2]iv2[2]iv3[1]out[2][2][1]iv1[2]iv2[2]iv3[2]out[2][2][2]iv1[2]iv2[2]iv3[3]out[2][2][3]iv1[2]iv2[2]iv3[4]out[2][2][4]iv1[3]iv2[1]iv3[1]out[3][1][1]iv1[3]iv2[1]iv3[2]out[3][1][2]iv1[3]iv2[1]iv3[3]out[3][1][3]iv1[3]iv2[1]iv3[4]out[3][1][4]iv1[3]iv2[2]iv3[1]out[3][2][1]iv1[3]iv2[2]iv3[2]out[3][2][2]iv1[3]iv2[2]iv3[3]out[3][2][3]iv1[3]iv2[2]iv3[4]out[3][2][4]Independent variable values must appear in ascending order (an error will be issued if this is not the case).
Alternatively, the independent variables may be defined using the Value <x> fields below.
Field: External File Column Number[LINK]
The column number (starting at 1) in the CSV file corresponding to this independent variable. As the values of the independent variables each repeat over a defined cycle, EnergyPlus will only read unique values from this column. EnergyPlus does not validate that the cycles are repeating correctly. In fact, the same data can be read by only defining each value once as it is first encountered:
iv1iv2iv3outputiv1[1]iv2[1]iv3[1]out[1][1][1]iv3[2]out[1][1][2]iv3[3]out[1][1][3]iv3[4]out[1][1][4]iv2[2]out[1][2][1]out[1][2][2]out[1][2][3]out[1][2][4]iv1[2]out[2][1][1]out[2][1][2]out[2][1][3]out[2][1][4]out[2][2][1]out[2][2][2]out[2][2][3]out[2][2][4]iv1[3]out[3][1][1]out[3][1][2]out[3][1][3]out[3][1][4]out[3][2][1]out[3][2][2]out[3][2][3]out[3][2][4]Field: External File Starting Row Number[LINK]
The row number (starting at 1) in the CSV file where the data for this independent variable begins. Any values in the same column below this row are considered part of the range.
Field: Value <x>[LINK]
If not reading from an external file, this field is repeated to capture the full set of values for this independent variable. These values must be defined in ascending order (an error will be issued if this is not the case).
Example IDF[LINK]
Documentation content copyright © 1996-2026 The Board of Trustees of the University of Illinois and the Regents of the University of California through the Ernest Orlando Lawrence Berkeley National Laboratory. All rights reserved. EnergyPlus is a trademark of the US Department of Energy.
This documentation is made available under the EnergyPlus Open Source License v1.0.