20. Spec to Commissioning Checklist · Page 1 of 7
Writing a Clear SPD Specification
Avoid vague "SPD to be provided" notes.

Include
- Standards basis (e.g. IEC 61643-11)
- Type per location
- System voltage / earthing system
- In / Iimp / Up targets
- Remote signaling requirement
- Backup protection requirements
Drawings
Show SPD symbols on the single-line with notes for lead length discipline.
