SFS 6000 is Finland's national standard for electrical installations — a direct adoption of the international IEC/HD 60364 series. On any data centre or infrastructure project in Finland, compliance is not optional: it is a legal requirement enforced by Tukes, the Finnish safety authority.
What it covers
- Part 1 — general principles, scope, fundamental protection, design methodology.
- Parts 3–4 — protection for safety: electric shock, thermal stress, overcurrent.
- Part 5 — selection and erection of equipment: cable sizing, earthing, distribution, switchgear.
- Part 6 — inspection, testing, and certification protocols.
Why it matters in data centres
Data centre electrical systems are complex and mission-critical. A single non-conforming installation — a miscalibrated protective device, an earthing fault — can violate Tukes requirements, create safety hazards, compromise equipment protection, and create liability in an incident. SFS 6000 defines the baseline every installation is verified against.
Key areas in a data centre context
Protective earthing
Protective devices must disconnect a fault within specified times (typically 0.4 s); poor earthing prevents this. SFS 6000 specifies maximum earth fault loop impedance (Zs), electrode sizing and verification, and earthing schemes (TN-S preferred in most data centres).
Overcurrent protection and selectivity
Breakers must protect against overload and short circuit and coordinate correctly — upstream devices must not trip before downstream ones, or a single fault can black out an entire hall.
Residual current protection
High-sensitivity RCDs (30 mA) protect people where contact is possible; lower-sensitivity devices (300–500 mA) serve equipment circuits to avoid nuisance trips. Both must be specified and tested correctly.
Cable sizing and installation
Cables must be sized for ampacity and voltage drop, protected against mechanical damage, and marked. Undersized or damaged cables mean overheating and fire risk.
Distribution boards and switchgear
Correct IP ratings, complete circuit identification, and access for Part 6 testing and maintenance.
The five defects we see most often
- Earthing impedance out of spec — measured Zs exceeds limits, requiring re-work.
- Non-coordinated protective devices — selectivity broken; cascading trip risk.
- Cable routing and identification errors — sizing or mechanical protection wrong.
- Missing or incorrect test certificates — no evidence of continuity, insulation resistance, or Zs testing.
- Switchgear labelling gaps — circuit identification missing; hazardous during maintenance.
All five leave fingerprints in the documentation before they become site problems — which is why a rigorous review of ITPs and test packs catches them early.
Part 6: testing and verification
Part 6 defines the verification protocol: visual inspection, continuity testing, insulation resistance, earth fault loop impedance, RCD functionality, and load testing. All testing must be witnessed, recorded, and certified — and your ITPs should specify exact methods, tolerances, acceptance criteria, and sign-off authority for each.
Practical implementation
For subcontractors and installers
- Use SFS 6000 as the baseline; do not cherry-pick requirements.
- Complete all Part 6 testing before handover — defects found at commissioning cost far more.
- Keep test certificates and instrument calibration records; they will be asked for.
- Reference Part 6 explicitly in ITPs, with traceability from every result to circuit, date, and operator.
For owners and main contractors
- Specify SFS 6000 compliance explicitly in the electrical design brief.
- Make Part 6 certificates a condition of payment.
- Have documentation independently verified before acceptance.
SFS 6000 alongside other standards
| Standard | Focus | Context |
|---|---|---|
| SFS 6000 | Electrical installation safety | Finnish legal requirement for all installations |
| EN 50600 | Data centre infrastructure | Industry best practice; complements SFS 6000 |
| Tukes guidance | Regulatory interpretation | How the authority applies SFS 6000 in practice |
In practice, most Finnish data centre projects follow SFS 6000 as the legal minimum plus EN 50600 as best practice.
SFS 6000 can feel abstract until a circuit won't trip correctly or an earthing measurement comes back out of spec the week before handover. If you want your electrical documentation checked against it before anyone else checks it for you, see how our reviews work or get in touch.
Sources: SFS (Finnish Standards Association) · Tukes · IEC 60364 series