Updated Reference Library ^{Version 3.12.0 : Feature 7433 11/03/2022}

Models of Reyrolle's Type 2DCC overcurrent and earth fault relays have been added to our reference library.

Scalable Vector Graphics (SVG) Export ^{Version 3.12.0 : Feature 7420 11/03/2022}

The SVG export facility has been improved and now supports Fault and IEC909 results. This means that when you export your single-line diagram in SVG format, and your diagram displays Fault or IEC909 results, those results will be included in and displayed by the SVG export.

Python Interface ^{Version 3.12.0 : Feature 7413 11/03/2022}

Our ERACS Python interface has been updated to v1.1.5.18.

Further information about this feature is available using the associated link below.

Associated Links:

• Python Documentation (https://www.eracs.co.uk/python/docs)

Arc Flash Risk Assessment Template ^{Version 3.12.0 : Feature 7402 11/03/2022}

An arc flash hazard warning label template, named ArcFlashHazardLabels_American_Custom3.dot, has been created that employs the arc flash warning symbol outlined in ISO 7010-W042.

Arc Flash Risk Assessment Template ^{Version 3.12.0 : Feature 7384 11/03/2022}

An arc flash hazard warning label template, named ArcFlashHazardLabels_American_Custom2.dot, has been created which is based on the advice presented in an infographic provided by a voting member of IEEE 1584 and CSA Z462 (Canadian Electrical Safety Standard) who authored a labelling section of the latter standard (Annex Q).

Python Interface ^{Version 3.12.0 : Feature 7366 11/03/2022}

The Multi-Loadflow Python interface has been enhanced and enables the messages raised by each Loadflow calculation to be written to a text file.

Updated Reference Library ^{Version 3.12.0 : Feature 7343 11/03/2022}

Models that represent the overcurrent and earth fault functions of Toshiba's GRL150 and GRL200 relays have been added to our reference library.

Updated Reference Library ^{Version 3.12.0 : Feature 7318 11/03/2022}

A model of Leroy Somer's LSA 56 BMDL145 / 4p alternator has been added to our reference library.

Arc Flash Risk Assessment module updated to support NFPA 70E-2021 ^{Version 3.12.0 : Feature 7313 11/03/2022}

The Arc Flash Risk Assessment module has been updated in line with NFPA 70E-2021. It is now possible to set the NFPA 70E Edition study parameter to '2021' in the Arc Flash study setup form. The PPE Table and Help file, available via the Report window and Detail form, have been updated accordingly. A Capacitor Hazard Analysis capability, based upon 70E-2021 Article 360 and Annex R, is not provided in this release but will be implemented in a forthcoming release.

Switch Group Manager ^{Version 3.12.0 : Feature 6937 11/03/2022}

The switch group facilities have been significantly improved with the inclusion of a Switch Group Manager, which provides these features:

• Switch groups can be created. Each group is provided a name, description and a list of switches that are members of the group.
• Switches can be members of multiple switch groups.
• Switches can be added to a group by selecting them in the single-line diagram or via their data entry form.
• When choosing to open/close a switch that is a member of a group, an option is provided that enables the action to be applied to all switches in the group(s).
• A switch group event has been added to Transient Stability, enabling all switches in a group to be opened, closed or toggled.
• A switch can be removed from the group making it no longer necessary to navigate the single-line diagram and edit the switch.

Scalable Vector Graphics (SVG) Export ^{Version 3.12.0 : Feature 6922 11/03/2022}

The SVG export facility has been improved and now supports Loadflow results. This means that when you export your single-line diagram in SVG format, and your diagram displays Loadflow results, those results will be included in and displayed by the SVG export.

IEC909 Improvements ^{Version 3.12.0 : Feature 6735 11/03/2022}

ERACS' IEC909 calculation has been significantly improved. It has been aligned with IEC 60909-0:2016 and 60909-0:2001 and includes several new features.

Editions of the Standard

Firstly, the major improvement is that the module now supports both IEC 60909:2016 and IEC 60909:2001. The inclusion of IEC 60909:2001 is really for backward compatibility and by default, the module will choose the IEC 60909:2016 edition of the standard.

The module still provides support for the 1988 edition. Again, that is for backward compatibility and for re-running any studies that you have previously performed.

A control, that is labelled Edition of Standard, has been added to the study setup windowl and enables you to choose one of these options:

• IEC 60909:2016
• IEC 60909:2001
• IEC 909:1988

Maximum and Minimum Fault Calculation

ERACS now enables you to perform 'maximum', 'minimum' and 'user-defined' fault level calculations.

A control, labelled C factor, has been added to the study setup panel and enables you to choose one of the following options:

• Max: maximum fault levels will be calculated using voltage factor c_max specified in the appropriate Voltage factor table according to the edition of the standard that has been selected. Impedance correction factors are calculated for synchronous machines and transformers (if 2016 or 2001 edition is selected).
• Min: minimum fault levels will be calculated using voltage factor c_min specified in the appropriate Voltage factor table according to the edition of the standard that has been selected. Impedance correction factors are set to unity.
• User-defined: the new set of Voltage Range controls will be enabled to allow you to define the voltage factor, c, to be employed.

Peak Short-Circuit Current Calculation Method

Two additional methods of calculating the peak short-circuit current, i_p, have been provided:

• Method B: Factor к (Kappa) is derived from the R/X ratio of the short-circuit impedance employed by the initial short-circuit current calculation.
• Method C (Kappa depends on system configuration): Factor к is derived from the R/X ratio of an equivalent frequency impedance seen from the short-circuit location and considers the type of fault and subsequent connection of the sequence networks.

Access to the new calculation methods is provided by an option that has been included in the study setup window. The option is labelled Peak Short-Circuit Current, i_p, Calculation Method and these options have been provided: 'C (Kappa depends on system configuration)', 'C (Kappa set to three phase short-circuit value)' and 'B'. By default, the option is set to 'C (Kappa depends on system configuration)'.

Impedance Correction Factor for Network Transformers, K_T

When Edition of Standard is set to 'IEC 60909:2016' or 'IEC 60909:2001' and C factor is set to 'Max', a transformer impedance correction factor, K_T, is calculated and applied to all network transformers.

Results Displayed on Single-Line Diagram

Summary Box and Busbar:

• Voltage Correction Factor.
• Nominal Voltage (kV).
• Initial Symmetrical Apparent Power (MVA).
• Symmetrical Breaking Capacity (MVA).
• X/R ratio (peak).
• R/X ratio (peak).
• X/R ratio (dc).
• R/X ratio (dc).
• Factor Kappa.
• Factor Kappa Product.
• Breaking Time (s).
• DC Current at Breaking Time (kA).
• Positive Sequence Driving Point Impedance (pu).
• Positive Sequence Driving Point Impedance Angle (°).
• Negative Sequence Driving Point Impedance (pu).
• Negative Sequence Driving Point Impedance Angle (°).
• Zero Sequence Driving Point Impedance (pu).
• Zero Sequence Driving Point Impedance Angle (°).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current in Phase 2 (kA).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current Angle in Phase 2 (°).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current in Phase 3 (kA).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current Angle in Phase 3 (°).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current to Earth (kA).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current Angle to Earth (°).

Grid Infeed:

• Identifier.
• Voltage Factor.
• Partial Initial Short-Circuit Current (kA).
• Partial Initial Short-Circuit Current Angle (°).
• Three Phase Fault Infeed (MVA).
• Three Phase Fault X/R Ratio.
• Single Phase Fault Infeed (MVA).
• Single Phase Fault X/R Ratio.
• Positive/Negative Sequence Resistance (pu/r).
• Positive/Negative Sequence Reactance (pu/r).
• Zero Sequence Resistance (pu/r).
• Zero Sequence Reactance (pu/r).

Synchronous Machine:

• Identifier.
• Voltage Factor.
• Power Factor.
• Impedance Correction Factor.
• Factor µ.
• Partial Initial Short-Circuit Current (kA).
• Partial Initial Short-Circuit Current Angle (°).
• Rated Current (kA).
• Corrected Positive Sequence Resistance (pu/r).
• Corrected Positive Sequence Reactance (pu/r).
• Corrected Negative Sequence Resistance (pu/r).
• Corrected Negative Sequence Reactance (pu/r).
• Corrected Zero Sequence Resistance (pu/r).
• Corrected Zero Sequence Reactance (pu/r).

Induction Machine:

• Identifier.
• Factor µ.
• Factor q.
• Partial Initial Short-Circuit Current (kA).
• Partial Initial Short-Circuit Current Angle (°).
• Rated Current (kA).
• Locked Rotor Current (kA).
• Locked Rotor X/R Ratio.
• Locked Rotor R/X Ratio.
• Positive/Negative Sequence Resistance (pu/r).
• Positive/Negative Sequence Reactance (pu/r).

Transformer:

• Identifier.
• Voltage Factor.
For two-winding transformers:
• Impedance Correction Factor.
For three-winding transformers:
• Impedance Correction Factor – Winding 1 to 2.
• Impedance Correction Factor – Winding 1 to 3.
• Impedance Correction Factor – Winding 2 to 3.

Transformer windings:

• Corrected Positive/Negative Sequence Resistance (pu/r).
• Corrected Positive/Negative Sequence Reactance (pu/r).
• Corrected Zero Sequence Resistance (pu/r).
• Corrected Zero Sequence Reactance (pu/r).

Synchronous Machine Power Factor

Facilities have been added to the synchronous machine data entry form that enable you to explicitly define the power factor that will be employed by the IEC909 calculation module to calculate the machine’s impedance correction factor, K_G.

Synchronous Machine Resistance

An option that enables you to choose the resistance that will be employed for synchronous machines during the calculation of the peak short-circuit current, i_p, has been added to the study setup window. The option is labelled Synchronous Machine Resistance for ip Calculation, and two choices have been provided: 'Fictitious resistance defined in the standard' and 'Stator resistance from library dataset'. By default, the option is set to 'Stator resistance from library dataset'.

Grid Infeed R/X Ratio

An option that enables you to choose the R:X ratio employed by grid infeeds has been added to the study setup window. The option is labelled Grid Infeed R/X Ratio and two options have been provided: '0.1; i.e. Rq = 0.1*Xq, Xq = 0.995*Zq' and 'Value provided in the grid infeed’s data entry form'. By default, the option is set to 'Value provided in the grid infeed's data entry form'.

Initial Short-Circuit Current for Two-Phase to Earth Studies

For two-phase to earth fault calculations, ERACS now calculates I"_kE2E, I"_k2EL2 and I"_k2EL3. All three values are written to the Excel formatted results file and can be selected for display on the single-line diagram.

IEC909 Results: Synchronous Machine ^{Version 3.12.0 : Feature 6642 11/03/2022}

The following synchronous machine results have been added for display on the single-line diagram after an IEC909 calculation has been performed:

• Identifier
• Voltage Factor
• Power Factor
• Impedance Correction Factor
• Factor µ
• Partial Initial Short-Circuit Current (kA)
• Partial Initial Short-Circuit Current Angle (°)
• Rated Current (kA)
• Corrected Positive Sequence Resistance (pu/r)
• Corrected Positive Sequence Reactance (pu/r)
• Corrected Negative Sequence Resistance (pu/r)
• Corrected Negative Sequence Reactance (pu/r)
• Corrected Zero Sequence Resistance (pu/r)
• Corrected Zero Sequence Reactance (pu/r)

Deleting Networks & Studies ^{Version 3.12.0 : Feature 6575 11/03/2022}

When deleting studies, it is possible to select multiple items using the standard techniques employed by Windows' selection controls:

1. Click the first item.
2. Press and hold CTRL.
3. Click each additional item to add to the selection.

1. Click the “from” item.
2. Press and hold SHIFT.
3. Click the “to” item to select the “from” through “to” items.

Switch Group Manager ^{Version 3.12.0 : Feature 6541 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.6937 (https://releasenotes.eracs.co.uk/version/3.12.0/6937)

IEC909 Data: Synchronous Machine Power Factor ^{Version 3.12.0 : Feature 6401 11/03/2022}

An IEC909 page has been added to the synchronous machine's data entry form. The page includes a field allowing you to define the power factor to be employed by the IEC909 calculation to calculate the machine's impedance correction factor, K_G.

IEC909 Results: Summary Box & Busbar ^{Version 3.12.0 : Feature 5989 11/03/2022}

The following extra IEC909 results have been provided for the Summary Box and Busbars:

• Voltage Correction Factor.
• Nominal Voltage (kV).
• Initial Symmetrical Apparent Power (MVA).
• Symmetrical Breaking Capacity (MVA).
• X/R ratio (peak).
• R/X ratio (peak).
• X/R ratio (dc).
• R/X ratio (dc).
• Factor Kappa.
• Factor Kappa Product.
• Breaking Time (s).
• DC Current at Breaking Time (kA).
• Positive Sequence Driving Point Impedance (pu).
• Positive Sequence Driving Point Impedance Angle (°).
• Negative Sequence Driving Point Impedance (pu).
• Negative Sequence Driving Point Impedance Angle (°).
• Zero Sequence Driving Point Impedance (pu).
• Zero Sequence Driving Point Impedance Angle (°).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current in Phase 2 (kA).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current Angle in Phase 2 (°).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current in Phase 3 (kA).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current Angle in Phase 3 (°).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current to Earth (kA).
• 2Ph-Eth Initial Symmetrical Short-Circuit Current Angle to Earth (°).

IEC909 Results: Summary Box & Busbar ^{Version 3.12.0 : Feature 5906 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.5989 (https://releasenotes.eracs.co.uk/version/3.12.0/5989)

IEC909 Data: Synchronous Machine Power Factor ^{Version 3.12.0 : Feature 5893 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.6401 (https://releasenotes.eracs.co.uk/version/3.12.0/6401)

IEC909: Study Setup ^{Version 3.12.0 : Feature 5879 11/03/2022}

An option that enables you to choose the R:X ratio employed by grid infeeds has been added to the study setup window. The option is labelled Grid Infeed R/X Ratio and two options have been provided:

• 0.1; i.e. Rq = 0.1*Xq, Xq = 0.995*Zq
• Value provided in the grid infeed’s data entry form

IEC909: Study Setup ^{Version 3.12.0 : Feature 5878 11/03/2022}

An option that enables you to choose the resistance that will be employed for synchronous machines during the calculation of the peak short-circuit current, i_p, has been added to the study setup window. The option is labelled Synchronous Machine Resistance for ip Calculation, and two choices have been provided:

• Fictitious resistance defined in the standard
• Stator resistance from library dataset

Grid Infeed Fault Levels ^{Version 3.12.0 : Feature 5803 11/03/2022}

ERACS now enables you to enter the maximum, minimum and 'other' fault levels for a grid infeed.

Facilities have been added to the Loadflow and IEC909 calculation setup panels that enable you to choose which fault level dataset should be employed by the grid infeeds in your single-line diagram.

Switch Group Manager ^{Version 3.12.0 : Feature 5784 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.6937 (https://releasenotes.eracs.co.uk/version/3.12.0/6937)

IEC909: Peak Short-Circuit Current Calculation ^{Version 3.12.0 : Feature 5765 11/03/2022}

Two additional methods of calculating peak short-circuit current, ip, have been provided:<

• Method B.
• Method C, where Factor Kappa is calculated depending on the system configuration.

IEC909: Support for IEC 60909:2016 & IEC 60909:2001 ^{Version 3.12.0 : Feature 5099 11/03/2022}

The IEC909 calculation has been updated to support IEC 60909:2016 and IEC 60909:2001.

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.6735 (https://releasenotes.eracs.co.uk/version/3.12.0/6735)

IEC909: Summary Box & Busbar Results ^{Version 3.12.0 : Feature 5034 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.5989 (https://releasenotes.eracs.co.uk/version/3.12.0/5989)

Grid Infeed Fault Levels ^{Version 3.12.0 : Feature 4405 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.5803 (https://releasenotes.eracs.co.uk/version/3.12.0/5803)

IEC909: Two-Phase to Earth Fault Current ^{Version 3.12.0 : Feature 3285 11/03/2022}

For two-phase to earth fault calculations, ERACS now calculates I"_kE2E, I"_k2EL2 and I"_k2EL3. All three values are written to the Excel formatted results file and can be selected for display on the single-line diagram.

IEC909: Peak Short-Circuit Current Calculation ^{Version 3.12.0 : Feature 3276 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.5765 (https://releasenotes.eracs.co.uk/version/3.12.0/5765)

IEC909: Support for IEC 60909:2016 & 60909:2001 ^{Version 3.12.0 : Feature 3258 11/03/2022}

The IEC909 calculation has been updated to support IEC 60909:2016 and IEC 60909:2001.

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.6735 (https://releasenotes.eracs.co.uk/version/3.12.0/6735)

Switch Group Manager ^{Version 3.12.0 : Feature 3122 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.6937 (https://releasenotes.eracs.co.uk/version/3.12.0/6937)

Switch Group Manager ^{Version 3.12.0 : Feature 3118 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.6937 (https://releasenotes.eracs.co.uk/version/3.12.0/6937)

IEC909: Support for IEC 60909:2016 & IEC 60909:2001 ^{Version 3.12.0 : Feature 2332 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.6735 (https://releasenotes.eracs.co.uk/version/3.12.0/6735)

Deleting Networks & Studies ^{Version 3.12.0 : Feature 2035 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.6575 (https://releasenotes.eracs.co.uk/version/3.12.0/6575)

IEC909 Results: Summary Box & Busbar ^{Version 3.12.0 : Feature 1950 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.5989 (https://releasenotes.eracs.co.uk/version/3.12.0/5989)

Switch Group Manager ^{Version 3.12.0 : Feature 1921 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.6937 (https://releasenotes.eracs.co.uk/version/3.12.0/6937)

Switch Group Manager ^{Version 3.12.0 : Feature 1613 11/03/2022}

Further information about this feature is available using the associated link below.

Associated Links:

• ERACS Reference No.6937 (https://releasenotes.eracs.co.uk/version/3.12.0/6937)