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Featured Suite

Transformer & Equipment
Testing Suite

A comprehensive collection of transformer diagnostic and commissioning calculators built to IEC, IEEE & IS standards. Perfect for power engineers, testing teams, and maintenance professionals.

Open Transformer Suite
✔Tan Delta (Dissipation Factor)
✔Oil Breakdown Voltage (BDV)
✔Dissolved Gas Analysis (DGA)
✔Transformer Turns Ratio (TTR)
✔Winding Resistance Temp
✔Insulation Resistance (IR)
✔Polarisation Index (PI)
✔CT Ratio & Accuracy Class
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Oil DGA AnalysisNew
IEC 60599 fault diagnosis
Winding Resistance TempNew
IEEE correction formula
Polarisation IndexUpdated
PI & DAR test evaluation
Short Circuit CurrentNew
3-phase fault calculations
Cable DeratingNew
Temperature & grouping factors
Earthing DesignUpdated
Touch & step voltage analysis
Reference

Formula Library

Essential engineering formulas at a glance

Electrical
Ohm's Law
V = I × R
Fundamental circuit relationship
Electrical
Active Power (AC)
P = V × I × cos φ
Real power in AC circuits
Electrical
Transformer EMF
E = 4.44 × f × N × Φm
EMF equation of transformer
Electrical
Tan Delta
tan δ = I_loss / I_charging
Insulation dissipation factor
Electrical
Turns Ratio
a = Vp / Vs = Np / Ns
Transformer ratio relationship
Electrical
Cable Impedance
Z = R + jX (Ω/km)
Complex impedance per unit length
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Knowledge Base

Engineering Articles

Testing & Commissioning8 min read
🛡️
Understanding Transformer Tan Delta Testing
A complete guide to tan delta testing for assessing transformer insulation condition and predicting failures before they occur.
Jun 2025Read More ↗
Diagnostics12 min read
🧪
Dissolved Gas Analysis: IEC 60599 Explained
How to interpret DGA results using Duval Triangle, Rogers Ratio, and IEC methods to diagnose transformer faults.
May 2025Read More ↗
Power Systems10 min read
💻
Cable Sizing: AS/NZS 3008 vs IEC 60364
Comparing two major cable sizing standards — when to apply each, derating factors, and how to select the right conductor.
May 2025Read More ↗
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