COMMERCIAL ELECTRICAL

Motor Inspections

• Verify that ampacities and sizing of components other than overload devices are based on table values rather than nameplate values.
• Verify that conductor ampacities for individual motors are at least 125 percent of table FLC.
• Check conductors supplying multiple motors for ampacities equal to at least the sum of FLC’s plus 125 percent of largest motor.
• Verify motor overload protection does not exceed permitted values.
• Verify that motor branch circuit, short circuit, and ground fault protection does not exceed permitted values.
• Verify that motor feeder short circuit and ground fault protection does not exceed permitted values.
• Check motor control circuits for proper over current protection.
• Verify that motor controllers are provided for motors and that they are of the proper type and have adequate ratings.
• Check MCC’s for proper ratings, protection, workspace, and dedicated space.
• Verify that motor disconnects are of the proper type and rating.
• Verify that controller disconnects are in sight of controllers, are readily accessible, and have adequate workspace.
• Verify that motor disconnects are in sight of motors, are readily accessible, and have adequate workspace, or that controller disconnects are lockable.

Air-Conditioning and Refrigerating Equipment Inspections

• Identify equipment subject to Article 440-Equipment containing hermetic refrigerant motor compressor(s).
• Identify the applicable nameplate information for the equipment.
• Verify that conductors supplying several units are adequately sized.
• Verify that branch circuit conductor sizes are adequate based on the applicable nameplate information.
• Verify that conductors supplying several units are adequately sized.
• Verify that branch circuit overload protection is provided and properly sized.
• Verify that branch circuit, short circuit, and ground fault protection is provided and properly sized.
• Verify that feeder short circuit and ground fault protection is provided and properly sized where applicable.
• Verify that controllers have adequate ratings where they are not part of listed multi motor or combination load equipment.
• Verify that disconnecting means have ratings adequate for the equipment.
• Verify that the disconnecting means are within sight and readily accessible from the equipment, and that working spaces are adequate.
• Verify that conductors, receptacles, cords, and over current devices for room air conditioners are properly sized.
• Check for receptacles and adequate lighting for servicing of mechanical equipment.

Transformer Inspections

• Identify transformers that are covered by Article 450.
• Verify that over current protection for transformers over 600 volts is provided and properly sized.
• Verify that over current protection is provided for transformer primary conductors.
• Verify that over current protection is provided for transformer secondary conductors.
• Check transformer installations for adequate ventilation and spacing from walls and obstructions.
• Check transformers for ready access or proper installation in the open or in hollow spaces.
• Check indoor dry type transformers for separation from combustibles or, based on ratings, installation in fire resistant rooms or vaults.
• Check outdoor dry type transformers for weatherproof enclosures.
• Verify that liquid insulated transformers are installed in accordance with the requirements for the location and type of insulating liquid.
• Check transformer vaults for adequate construction, access, ventilation, and drainage, and for foreign systems in vaults.

COMMERCIAL AND INDUSTRIAL
SERVICES, FEEDERS AND BRANCH CIRCUITS

Service Inspections

• Verify that each building or structure has only one service, or if more than one, that additional services are justified.
• Verify that each service drop or lateral serves only one set of service entrance conductors, or if more than one, that the additional sets are justified.
• Check clearances from building openings, grade, roadway, roofs, and swimming pools.
• Verify that the point of attachment for an overhead service drop is adequate and will provide minimum clearances.
• Verify that masts used as supports for service drop conductors have adequate strength and are not used to support other conductors or equipment.
• Verify that supports for service conductors passing over a roof are adequate and substantial.
• Check underground conductors for adequate burial depth and protection.
• Check aboveground conductors and cables for adequate supports and protection from physical damage.
• Verify that wiring methods for service entrance conductors are suitable.
• Verify that service raceways are arranged to drain and that service heads are rain tight and properly located.
• Check service conductors for adequate size and rating.
• Verify that service equipment is identified as suitable for the use.
• Verify that a service disconnecting means is provided, suitable, marked, and located outside or inside nearest point of entrance of the service conductors.
• Verify that service over current protection is provided, properly sized, and part of or adjacent to the disconnecting means.
• Verify that service disconnects are grouped together and limited to six in any one location.
• Check ratings of service disconnecting means.
• Check for equipment connected to the supply side of the service disconnecting means and over current protection.
• Verify that GFP is supplied where required, and obtain a written record of performance testing.

Feeder Inspections

• Verify that feeders are at least equal to the minimum permitted size.
• Verify that feeder conductors, including any neutral conductors, are adequate for the load.
• Check over current device and feeder conductor sizing for continuous and noncontinuous loads.
• Check wiring methods for suitability.
• Check feeders with over current protection rated at 1000 amperes or greater for GFP for equipment, if required.
• Verify that disconnects are provided at separate structures for feeders running between structures.
• Verify that disconnects at separate structures are properly rated, located, grouped, and identified.
• Verify that disconnects at separate structures are properly rated, located, grouped, and identified.
• Verify that any outside feeders use appropriate wiring methods and are properly supported and arranged to drain.
• Check any outside feeders for adequate supports, clearances, and mechanical protection.
• Verify that feeders tapped from transformers are properly protected by over current devices.
• Check panelboards supplying or supplied by feeders for over current protection, grounding, proper enclosures, and number of over current devices.

Branch Circuit Inspections

• Verify that wiring methods used are appropriate for the conditions and occupancy.
• Check panelboards for proper over current protection and limitations on number of over current devices.
• Check multi outlet and individual branch circuits for proper ratings.
• Check conductors and over current protection for consideration of continuous and noncontinuous loads, multi outlet loads, and minimum ampacity and size.
• Check branch circuits supplying receptacles and other outlet devices for permitted ratings of circuits and receptacles.
• Verify that branch circuit loads do not exceed maximum permitted loads.
• Verify that branch circuits supplying motors are sized according to Article 430 or 440, and that inductive lighting loads are based on ballast ratings.
• Verify that branch circuits are used to supply only permissible loads based on their ratings.
• Verify that the number of branch circuits is adequate and that the load is evenly proportioned among the branch circuits.
• Check for compliance with branch circuit voltage limitations.
• Verify that branch circuits for specific loads meet the requirement of the applicable articles.
• Check for proper use and identification of multi wire branch circuits.
• Check for required receptacles and lighting for mechanical equipment.
• Check for required outlets or receptacles for show windows and signs.
• Verify that receptacles are provided for all cord and plug connected appliances, and where flexible cords are used.
• Verify that GFCI protection is provided for receptacles in bathrooms and on rooftops.
• Verify that disconnects are provided at separate structures for branch circuits running between structures.
• Check for adequate size and clearances for outside branch circuits.

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