Manufacturer’s Label

Depending on the age and manufacturer, you may see different information on the label. Photograph the label, especially the parts with amperage rating and bonding diagrams. Here is the information you will look for:

  1. The amperage rating of the panel. This rating must not be less than that of the main disconnect. This is the most important information on any label.
  2. The type of panel. This is a number code that corresponds to the locations in which the panel is designed to be installed (interior, exterior, raintight, rain resistant, rain protected, etc.

EXPOSURE RATINGS

Type 1, rated for indoor use primarily to provide a degree of protection against limited amounts of falling dirt.

Type 3R, rated for outdoor use primarily to provide a degree of protection against rain, sleet and damage from external ice formation.

Type 3S, rated for outdoor use primarily to provide a degree of protection against windblown dust, rain and sleet; external mechanisms remain operable while ice-laden.

Type 4, rated for indoor or outdoor use primarily to provide a degree of protection against splashing water, windblown dust and rain, hose-directed water, and damage from external ice formation.

Type 4X, rated for indoor or outdoor use primarily to provide a degree of protection against splashing water, corrosion, windblown dust and rain, hose-directed water, and damage from external ice formation.

Type 6, rated for indoor or outdoor use primarily to provide a degree of protection against hose-directed water, the entry of water during occasional temporary submersion at a limited depth, and damage from external ice formation.

Type 12, rated for indoor use primarily to provide a degree of protection against circulating dust and falling dirt.

Type 12K, rated for indoor use primarily to provide a degree of protection against circulating dust, falling dirt and dripping non-corrosive liquids.

Type 13, rated for indoor use primarily to provide a degree of protection against dust and spraying of water, oil and non-corrosive coolant

3.  Grounding and bonding diagram- important in identifying the bonding screw.

4.  The listing agency certifying that the equipment complies with manufacturing standards, typically ANCE, UL, or may be both.
Whether it is designed as service equipment or a distribution panel
.

5.  The number of phases and voltage for which it as designed- typically single phase 120/240
.

6.  The number of circuits it is designed to contain. This means full size circuit breakers. This number may be improperly exceeded if duplex, triplex or quadplex breakers are used. Lighting and appliance branch- circuit panelboards are allowed a maximum of 42 poles. That’s 42 switch handles.

(for "panelboard" definition, see Types of Enclosures in INSPECTOR REFERENCE of ELECTRICAL SYSTEM).

7.  The maximum overcurrent device short circuit voltage- typically 10,000v.

 

Check for:

  • Amperage rating defects:
    • Main disconnect must be rated greater than the:
    • Service entrance conductors
    • Cabinet;
  • Non-compliance with listed information.

Circuit Directory

The Circuit Directory should be in place, legible, and accurate. If it looks older than the electrical work you see, recommend confirmation by a qualified electrical contractor.