Introduction
An electrical designer working in Russia and India or with international projects encounters three standards systems:
- PUE (Electrical Installation Code, 7th ed.) — Russia and CIS countries
- IEC 60364 — international standard, basis for European norms
- IS 732 (Indian Standard, adopted from IEC 60364) — India
Although IS 732 is based on IEC 60364, significant differences exist in practice. GorkyCAD supports calculations per all three systems — with automatic switching.
Comparison table
| Parameter | PUE (Russia) | IEC 60364 | IS 732 (India) |
|---|---|---|---|
| Nominal voltage | 230/400 V ±10% | 230/400 V ±10% | 230/400 V (50 Hz) |
| Voltage drop limit | 5% from MDB | 3% (lighting), 5% (other) | 3% (lighting), 5% (other) |
| Cable sizing basis | PUE tables 1.3.4-1.3.6 | IEC 60364-5-52 | IS 732, table 5 |
| Iz 2.5 mm² Cu | 27 A (3-core, in chase) | 27 A (method C) | 27 A (method C) |
| Overcurrent protection | Ch. 3.1 | IEC 60364-4-43 | IS 732 Section 4 |
| RCD mandatory | Cl. 7.1.71 (bathroom, sockets) | IEC 60364-4-41 | IS 732 (≤20A sockets, wet areas) |
| Earthing | TN-C-S, TN-S | TN, TT, IT | TN-S (preferred) |
| Selectivity | Recommended | IEC 60364-5-53 | IS 732 Section 5 |
| Lightning protection | Separate standard | IEC 62305 | IS/IEC 62305 (adopted) |
| S/C current calc | GOST 28249 | IEC 60909 | IS 13234 (based on IEC 60909) |
Key calculation differences
Cable current ratings
For 2.5 mm² copper, 3-core:
- PUE (in chase, brick): 27 A
- IEC 60364 (method C): 27 A
- IS 732 (method C): 27 A
Voltage drop
- PUE: single 5% limit for everything
- IEC/IS: split — 3% lighting, 5% other
A lighting circuit at 4.5% passes PUE but fails IEC/IS (needs 3%).
RCD protection
- PUE: mandatory for socket circuits, bathrooms. Type A recommended since 2020.
- IS 732: mandatory for all ≤20A sockets in residential + all wet-area sockets. Type A recommended.
- IEC 60364 (Germany): RCD ≤30 mA mandatory for all socket circuits ≤32 A.
→ IS 732 is generally stricter than PUE in coverage.
Earthing system
- Russia: TN-C-S dominant (combined PEN at input, split at MDB). PUE permits.
- India: de-facto standard — TN-S with separate N and PE throughout. IS 732 recommends TN-S for new installs.
- IEC: recognizes all systems, TN-C-S has usage restrictions.
→ For Indian projects: PEN conductor not allowed after separation point. Always run separate N and PE.
Terminology differences
| Russian (PUE) | English (IEC) | हिन्दी (IS 732) |
|---|---|---|
| Автоматический выключатель | Circuit Breaker (MCB) | परिपथ विच्छेदक (MCB) |
| УЗО | RCD | अवशिष्ट धारा युक्ति (RCD) |
| ГРЩ | Main Distribution Board (MDB) | मुख्य वितरण बोर्ड (MDB) |
| Сечение | Cross-Sectional Area (CSA) | अनुप्रस्थ काट क्षेत्र (CSA) |
How GorkyCAD simplifies work
- Country/standard selection at project creation — all norms auto-configured
- Standard switching for existing projects (e.g., started per PUE, client requested IS 732)
- Automatic recalculation on standard change
- Difference highlighting (where norms diverge)
- Trilingual BOMs (Russian/English/Hindi)
For engineers working on export or with Indian clients, this saves hours of manual recalculation and cross-checking.
Frequently asked questions
Is this article free?
Yes, all articles and calculators are completely free.
Yes, all articles and calculators are completely free.
Where can I run calculations?
The site offers 21 free calculators: cable sizing, breakers, RCD, voltage drop and more.
The site offers 21 free calculators: cable sizing, breakers, RCD, voltage drop and more.
How do I prepare an electrical project?
In GorkyCAD Pro: plans, panels, calculations and a PDF set for free.
In GorkyCAD Pro: plans, panels, calculations and a PDF set for free.
Found an error in the article?
Write to hello@gorkycad.pro — specialists will review and correct it.
Write to hello@gorkycad.pro — specialists will review and correct it.