SolarpunkHomes
Sign inCall us · +44 7510 081687
Solar
Solar · For traders

Do solar PV systems need surge protection devices?

Short answer

Usually yes. MIS 3002 says BS 7671 reg 443.4.1 applies: overvoltage protection is required where consequences are serious, and in all other cases must still be fitted unless the owner accepts the risk. Do not assume the inverter's internal protection is enough. Where a lightning protection system exists, coordinate SPD type and bonding under BS EN 62305.

Last checked 24 September 2026 · 1 source

In more detail

  • MIS 3002 cl.5.3.3 overrides the IET CoP 6.2 lightning risk-assessment decision.
  • Record owner's written decision if declining SPDs.
  • Maintenance: check integrity of fuses and surge protectors at intermediate/full visits (MIS App F).
  • DC-side SPD selection (Type 1/2, Ucpv) depends on array voltage and LPS - verify in CoP.

The facts, dated

  1. 01
    BS 7671 regulation governing SPD provision cited by MIS 3002 — 443.4.1

    standard · UK · checked 24 September 2026 · MCS

Sources

Last checked: 24 September 2026