Chart

Layered SPD placement map for Canadian services

Map common Type 1, Type 2, Type 3, PV, EV, and point-of-use surge protection placement concepts.

Chart boundary

Does not select an SPD, approve installation location, replace product instructions, or prove protection coordination.

one line layered spd map

Layered surge zones

The map shows why service entrance, panel, equipment, and point-of-use protection are different layers.

Scopeprotection and fault currentX-axisservice to load pathY-axisSPD layerReviewAnnualNextPanel Enclosure NEMA/CSA Type Ratings
Layered surge zonesType 1 / servic...Incoming serviceutility exposureType 2 / panel ...Distributionmain paneloutdoor and inv...PV / EV equipmentcharger or inverterType 3 / point ...Equipment and si...sensitive loads
The map shows why service entrance, panel, equipment, and point-of-use protection are different layers.
Type 1 / service layerIncoming service
  • utility exposure
  • service equipment
  • bonding path
Type 2 / panel layerDistribution
  • main panel
  • subpanel
  • PV/EV equipment
outdoor and inverter layerPV / EV equipment
  • charger or inverter
  • AC/DC rating match
  • product instructions
Type 3 / point of useEquipment and signal
  • sensitive loads
  • controls
  • data/signal circuits
Lead lengthshort and bonded

Product instructions govern installation.

Protected zonelayered, not universal

One SPD does not protect every pathway.

Decision reference

Show where surge protection discussions occur across service, distribution, branch, equipment, PV, and EV zones.

Reference basis: Canadian public-building SPD guidance, Canadian standards-notice context, and panelboard manufacturer SPD application materials.
MethodBest fitWatch pointHandoff
Service or line sideIncoming transient exposureEquipment listing and service rulesSPD manufacturer data
Panel SPDBranch circuit distribution layerBreaker, bonding, and lead length requirementsPanelboard data
PV or EV equipment SPDOutdoor inverter, charger, and DER exposureAC/DC ratings and product listingProduct instructions
Point-of-use or signal SPDSensitive plug-in loads, controls, data, and signal circuitsDoes not replace upstream protectionEquipment manual

Use notes

  • Use this chart as a planning and conversation aid only.
  • Confirm current utility requirements, product markings, manufacturer instructions, and local authority requirements before field work.
  • Use the linked calculator or table when the task needs project-specific arithmetic.

Reference sources

Open the underlying public references before treating the chart as project guidance.