Table

Multimeter CAT Ratings and Use Locations

Multimeter CAT Ratings and Use Locations reference with assumptions and boundary notes.

Reference boundary

Meter marking reference only. It does not select test equipment, authorize energized work, or replace safety procedures and product instructions.

Reference table

Decode common meter category markings by electrical environment and label-reading context.

Reference basis summarizes common CAT marking categories used in meter manufacturer safety literature.
CAT ratingCommon contextExposure summaryBoundary
CAT IProtected electronic circuitsLowest transient-energy category in this comparisonNot a building distribution measurement reference
CAT IIPlug-connected loads and receptacle-connected equipmentLoads connected to fixed wiring through outletsConfirm the meter voltage rating and leads
CAT IIIDistribution panels, feeders, and fixed equipmentHigher-energy building distribution measurementsRequires matching meter, leads, PPE, and work procedure
CAT IVService entrance, utility connection, and outdoor service conductorsHighest transient-energy category in this comparisonUtility/service work needs qualified procedures and equipment
Use notes
  • Use this table for preliminary reference and arithmetic checks only.
  • Confirm equipment ratings, product markings, installation conditions, utility requirements, and the local authority requirements before design or field use.