Action Level:

Action levels define the emergency levels associated with the amount of time a piece of line section equipment can maintain a specific current (Amps) without thermal failure:

The definition of the number of minutes associated with each Action Level is defined within the Thermal Ratings database.


Each piece of Equipment located within a Line Section will carry with it a property used to indicate the User that has 'Approved' the ratings associated with the Equipment.

Calculation Method:

Calculation Methods define the Method used during the thermal ratings calculations of Line Section Equipment. Calculation Methods relate to the ambient values, associated with Parameter Sets, that are to be used during thermal rating calculations. Every Line Section is assigned a Calculation Method (i.e. Non-PP7, PP7, PP8). Each "Parameter Set" is assigned ambient values for every Calculation Method. When equipment thermal ratings are calculated the chosen Parameter Set's values associated with the Calculation Method assigned to the equipment are used to determine the thermal ratings.


Each Substation must be assigned to the Company which owns it.


Overhead wire is comprised of a variety of possible Conductors/Types of Wire. Each Conductor has propreties used to define it and specify the properties needed to calculate an associated Wire's Thermal Ratings.


A Division within the organization to which Line Sections / Substations and the associated Line Section Equipment belong. Every Line Section, when created, will be assigned a Division. The accessibility of Line Sections and their Equipment are defined by the Divisions to which they belong and the Role in which the logged on User is assigned. See User Roles for how a Thermal Ratings Administrator can manage a User's accessibility to the system. The Administrator can setup the User Roles to comply with Federal Energy Regulatory Commission (FERC) regulations requiring the separate management of equipment in disparate Divisions.

End Point:

A named terminus of a Line Section. There are two type of end points: Substation and Terminal. A Substation within the Thermal Ratings program is the virtual equivalent of a physical Substation within the electric grid. Within a Substation there exists substation equipment containers:


A device within a Line Section which can limit the amount of current the Line Section may carry. Equipment is assigned, in an ordered fashion, to Line Sections.

Equipment Container:

Equipment within the program can not exist on its own. All equipment must be contained within an 'Equipment Container':

Within a container the equipment is manually ordered by the user via drag 'n drop within the user interface on the main Line Sections form.
Note: A piece of Equipment may exist in only a single Container at a time.

Equipment Type:

Each piece of Line Section Equipment is, by definition, of a particular type. Equipment types define the specifications to associate and the equations which are used to calculate the thermal ratings of the Equipment.

Sample Equipment Types:

In-Service / Out-of Service dates:

In-Service and Out-of-Service dates can be assigned to each piece of Equipment. The assignment of these dates allow for historical and predictive assessment of a Line Section's limiting thermal ratings; which equipment constitutes the limiting elements for a Line Section's electrical capacity.

Limiting Factor:

The determination of which electrical components within a line section represent the "Limiting Factors" for power transmission. The User has the ability to manually override the calculated thermal limits produced by the program. A Use Precalculated values flag, settable by the User, will determine if such manually entered data will be used in place of calculated values when determining limiting factors and running thermal ratings reports.

Line Section:

A named group of equipment manually ordered by the user. A line section has between one and two end points inclusive.

Line Section Categories:

Line Sections are separated into two distinct categories:

There are four filters which act like Line Section Categories: You can edit the Equipment located within these 'Filter' categories, but you can not Drag 'n Drop into or out of the 'Filter' Catgories. You can only Drag 'n Drop within the 'Line Section' and 'Substation' Categories.

Substation Phase Shifter Type:

Equipment containers known as Substation Phase Shifters contain equipment within substations. Each of these Phase Shifter equipment containers are assigned, by the user, a Type. The list of possible Phase Shifter Types is managed by the Thermal Ratings Administrator (see the View menu).

Substation Transformer Type:

Equipment containers known as Substation Transformers contain equipment within substations. Each of these Transformer equipment containers are assigned, by the user, a Type. The list of possible Transformer Types is managed by the Thermal Ratings Administrator (see the View menu).


The logfile is used for two main purposes:


Overhead wires are comprised of Conductors, and conductors are made up of a variety of different materials (i.e. Aluminum, Steel and Copper). Each material has associated factors that are used by the equations when calculating the associated equipment's thermal ratings: Solar Absorptivity and Emissivity.

Parameter Set:

Parameter Sets are used to specify the ambient values to be used within the equations when the thermal ratings of equipment are calculated: Ambient temperatures and wind velocity.


There are a number of reports that can be run from within the program:

In addition to being able to be printed, these reports can also be exported to a Portable Document Format (.pdf) file. Exporting to .pdf is accomplished by clicking on the export to .pdf button on the Report Viewer window.


Each Substation and Line Conductor Section must be associated with the physical state in which is resides (i.e. New Hammpshire, Connecticut). There is a State Filter on the main window that can be used to limit the Line Sections that are included within the tree view of Line Sections.


A Substation is a named container that contains Substation Components.

Substation Components:

Each Substation can contain a variety of substation components. Each component can then contain Equipment.


A Temperature is a defined set of temperature values (degrees Celsius) across a set of Action Levels.


A Terminal is a pseudo-Substation. Its purpose is to enable a Line Section to start or end at a name End Point.

Transformer Type:

A piece of Line Section Equipment known as a Transformer can be assigned a variety of Transformer Types. For example: Oil Filled or Compound. Each type can be assigned a calculation factor for each Action Level. Some versions of the software utilize these calculation factors within the thermal ratings equations when calculating the ratings of Transformer equipment.

User Preferences:

There are program wide settings that a user, depending on their Access Privileges, is allowed to adjust. The types of settings are:

User Roles:

Each User of the software will be assigned access privileges by the Thermal Ratings Administrator via the User Roles interface/window. A User Role relates directly to the Microsoft Windows® Active Directory (AD) Groups. Each Role's name must match the name of an Active Directory Group. The AD Groups to which the currently logged on User belongs will be used to determine the access privileges the User has within the software. The name of an AD Group is matched to the known User Role names within the software to determine to which Role the user belongs. As far as access rights to the underlying Microsoft SQL Server® database, the access to the appropriate stored procedures is not managed from with the Thermal Ratings software. As such, it must be managed at the SQL Server level via an external application/program like Microsoft's SQL Server Management Studio. It is the responsibility of your internal Database Administrator to setup and maintain the appropriate SQL Server access privileges. User Role access rights to Line Sections, Substations and Line Section Equipment are based on the Division in which the afore mention objects reside. For example: A user may have the right to update Equipment within the 'Transmission' division, but may not have the right to update Equipment within the 'Generation' division.

Caution: Do NOT remove the Access Privilege to 'Write' User Roles from ALL User Roles. If you do, you will no longer be able to update any User Roles!


Every Line Section must be assigned a voltage; Substation Transformers are assigned two distinct voltages: One for the High-Side and one for the Low-Side of the transformer. By assigning voltages to each Line Section, the display of the thermal ratings can be in either Amps or MVA.

White Papers:

White Papers are documents related to the Application to which you may want users to have easy access. There is a White Papers folder associated with this Application in which you can store such documents. The location of the folder is customizeable via the Preferences window. Easy access to the folder is accomplished via the Help Menu. Opening of a White Paper from within this Application uses the MS Windows® file type associations. I.E. .pdf files are normally assigned to be opened with Abobe Acrobat Reader®.