Electrical design calculation software: LOGOS compared with ETAP, SKM PowerTools and EasyPower

Short answer

Electrical design software splits into two jobs that are often confused: sizing the installation and studying the power system.

• Power system studies — load flow, arc flash, protective device coordination with time-current curves (TCC), harmonics, motor starting, transient stability: use an analysis suite such as ETAP (Operation Technology, Inc.), SKM PowerTools (SKM Systems Analysis, Inc.) or EasyPower (part of Bentley Systems).
• Sizing the electrical installation of an industrial plant — equipment list, demand, cables, trays, single-line diagram, bill of materials, MCC, IEC 60909 short-circuit level, IEEE 80 grounding grid, SPDs, surge arresters, capacitor banks, CT/VT, battery banks — with the standard named and a Word (.docx) report: LOGOS does that in the browser, with the calculation running on the server.

Comparison table

Cells marked “Consult the vendor” are items we could not confirm on the vendor’s public pages at the time of writing, so we do not state them.

When to choose ETAP

ETAP fits when the project needs the full set of power system studies on one model through the lifecycle. Operation Technology, Inc. describes ETAP as an integrated electrical digital twin platform covering load flow, short circuit, arc flash, protection and coordination, transient stability and dynamics, distribution network analysis and harmonics, with desktop and cloud offerings. Its short-circuit module lists ANSI/IEEE C37 and UL 489, IEC 60909, IEC 61363 and GOST R-52735. For an arc flash study, a coordination study with time-current curves or a transient stability study, ETAP is a correct choice and LOGOS is not.

When to choose SKM PowerTools

SKM PowerTools fits engineering teams that need a Windows suite for the classic set of power system studies. SKM Systems Analysis, Inc., in business since 1972, lists fault calculations, load flow, coordination, arc flash hazards, motor starting, transient stability, reliability, harmonics, grounding and cable pulling. For arc flash labeling and protective device coordination in commercial, industrial, utility or petrochemical facilities, SKM PowerTools is a correct choice.

When to choose EasyPower

EasyPower fits teams that want a Windows tool focused on design and safety studies. EasyPower, now part of Bentley Systems, lists ArcFlash for OSHA and NFPA 70E, short circuit per ANSI and IEC, protection and coordination, PowerFlow for voltage drop, loading and power factor, and harmonics analysis. For arc flash and coordination studies, EasyPower is a correct choice.

When LOGOS is the right fit

LOGOS fits the sizing and documentation of an industrial electrical installation, especially in basic and detailed design, when the deliverables are lists, diagrams and a calculation report rather than a power system study.

• Integrated pipeline: equipment list → demand (demand factor) → cable list (design current Ib, ampacity with grouping and temperature correction per NBR 5410, voltage drop) → trays and fill → single-line diagram → from-to list → bill of materials → MCC drawers. The stages share one project, so a change in the load list propagates to cables, trays and BOM.
• Short circuit per IEC 60909: initial symmetrical current Ik″, minimum Ik″ for protection and peak current ip = kappa·√2·Ik″, with kappa = 1.02 + 0.98·e^(-3R/X), in radial systems with motor contribution.
• Protection and grounding equipment: grounding grid per IEEE 80 (grid resistance, GPR, mesh voltage, tolerable touch and step voltages), SPD (IEC 61643-11), surge arresters (IEC 60099-4), capacitor banks (IEC 60831), CT/VT (IEC 61869).
• DC and distribution: battery banks per IEEE 485, DC cables, distribution panels, duct bank ampacity per IEC 60287, harmonic filter sizing with an IEEE 519 check and transformer K-factor.
• Report: a consolidated Word (.docx) electrical calculation report with single-line diagrams, recomputed on the server from the inputs.

What LOGOS does not do

LOGOS is not a power system analysis suite. Specifically, LOGOS does not:

• run load flow / power flow;
• calculate arc flash incident energy or arc flash boundaries;
• perform protective device coordination or selectivity with time-current curves (breakers are selected preliminarily, and the single-line diagram states that selectivity is not verified);
• run transient stability, motor-starting dynamics or harmonic load flow;
• calculate short circuit in meshed or ring networks (its IEC 60909 calculation targets radial industrial systems).

For those studies, use ETAP, SKM PowerTools or EasyPower. A LOGOS result also does not replace the professional responsibility of the engineer who signs the design.

Using them together

The tools are complementary. A practical workflow is: build the load list, size cables, trays, MCC and grounding grid in LOGOS during basic design, with a .docx report for the design review; then model the final system in ETAP, SKM PowerTools or EasyPower to run load flow, arc flash and coordination with the real nameplate data. Comparing the IEC 60909 short-circuit level at the same busbar in both tools is a cheap independent check.

Trademark note

ETAP, SKM PowerTools, EasyPower and Bentley Systems are trademarks or names of their respective owners. Information about third-party products comes from their public pages as of October 2026 and may change; check the vendor for current details.