Electrical Standards for Hallways and Outlets

Hallways and Receptacle Outlets

• Hallways in dwellings 3000 mm or more in length require at least one receptacle outlet.
• Show windows need one receptacle for each 3600 mm of linear width, installed directly above.
• Individual outlets for heating, air-conditioning, and refrigeration equipment must be at the same level as the equipment, within 7600 mm.

Required Lighting Outlets

• Lighting outlets are mandatory in habitable rooms, hallways, and stairways.
• Attached and detached garages with electric power also require lighting outlets.
• Interior stairways with six or more risers necessitate lighting outlets.
• Lighting is needed in storage spaces, equipment spaces, and guest rooms or suites.

Feeders: Minimum Rating and Size

• Feeders must have an allowable ampacity of noncontinuous load plus 125% of continuous load.
• For systems with 600 volts or less, feeders’ ampacity should be equal to or greater than that of the service and support loads of 55 amperes or less.

Branch Circuit, Feeder, and Service Calculations

• Voltages for calculations include nominal voltages such as 115V, 230V, 600V, etc.
• An ampere under 0.5 can be ignored in calculations.
• Heavy-duty lampholders have a minimum outlet calculation of 600VA.
• Sign and outline lighting outlets calculated at 1200VA.
• Show windows calculated at 200VA per 300 mm.
• Track lighting adds 150VA for every 600 mm.
• Receptacle loads in banks and office buildings calculated at 28VA/m².

Lighting Load Demand Factors

• Demand factors vary according to occupancy, influencing the lighting load calculation.
• For Dwelling Units: First 3000VA at 100% factor, 3001 to 120,000VA at 35%, over 120,000VA at 25%.
• Hospitals have reduced demand factors beyond 50,000VA (20%).
• Warehouses have strict load calculations for under and over 12,500VA.

Electric Clothes Dryers

• Each dryer in a dwelling must have a load of at least 5000 watts or its nameplate rating.

Overcurrent Protection

• Circuit breakers for overcurrent protection in three-phase circuits must include a minimum of three relay elements.
• Fuses connect in series with each ungrounded conductor.

Grounding and Bonding Requirements

• An effective ground-fault current path is mandatory for safety, ensuring fault current travels back to the source.
• Grounding of electrical systems and equipment limits voltage from lightning or contact with high-voltage sources.
• Bonding connects non-current carrying conductive materials to create an effective path for ground fault currents.
• Connections must be done using secure methods such as welding or tested clamps; soldered connections are not allowed.

Grounding Electrodes

• Permitted grounding electrodes include metal underground water pipes and metal frames of buildings.
• Common grounding electrode conductors need to be appropriately sized based on the type of metal.

Equipment Grounding Conductors

• Non-current carrying metal parts of fixed equipment must be grounded if within specified distances to the ground or other grounded objects.
• Equipment such as switchboard frames, motor frames, and various types of electrical equipment must maintain effective grounding.

Exemptions from Grounding

• Certain circuits, like those for electric cranes over combustible materials and in healthcare facilities, are not grounded for safety reasons.