Short-Circuit Calculation Quick Reference Card
Free download · 85 × 54mm (credit card size)
Carry the essential IEC 60909 short-circuit calculation formulas in your pocket. The front covers the initial symmetrical short-circuit current formula I"k = c × Un / (√3 × Zk), the voltage factor c table for LV (max 1.05/1.10) and HV (max 1.10), impedance correction factors KT (transformer), KG (generator), and KS (motor), plus three-phase, line-to-line, and single-phase fault equations side by side. The reverse provides peak current ip = κ × √2 × I"k with the κ factor table by R/X ratio, thermal equivalent short-circuit current Ith formula, and a quick reference of 10 common LV transformer impedances (kVA → %Zk). QR code links to ECalPro Short-Circuit Calculator.
What's Included
How to Print
- ●Recommended paper: 250–300gsm cardstock
- ●Print double-sided, flip on short edge
- ●Cut along crop marks with a paper trimmer
- ●Laminate with 80–125 micron pouches for durability
- ●Fits in wallet, toolbox, or pocket
Try the Interactive Calculator
Need precise calculations beyond quick reference? Try our free online calculator with full clause references and professional report output.
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Frequently Asked Questions
What paper should I print this on?
Print on 250–300gsm cardstock for durability. Use duplex (double-sided) printing and cut along the crop marks. Laminate with 80–125 micron pouches for long-term site use.
Can I distribute this to my team?
Yes. All ECalPro reference cards are free to download, print, and distribute within your organization. Keep the ECalPro branding and QR code intact.
What standard does this reference?
This card references IEC 60909-0:2016 for short-circuit calculation methodology and IEEE C37.13 for LV switchgear duty ratings.
How often is this updated?
Updated when IEC 60909 or IEEE C37 standards are revised. Current card reflects the latest editions.