Are you looking for electrical services from load calculations to filing?
Consolidated Edison, Inc. provides electricity for most homes and businesses in New York City, and customers must meet several requirements before connecting to the service. A load calculation must be carried out for the entire property, and the results are then used to fill an electrical load letter. Finally, the service connection is filed with Con Edison, who will install a power meter once all requirements are met.
Electric current can deliver large amounts of energy in an instant, and modern power grids connect generation plants and buildings with minimal losses. However, since the Con Edison grid is shared by thousands of consumers, the company must make sure that nobody uses a risky connection. If a major electrical fault occurs in a building, it can leave a very large area without power.
During the design process, electrical engineers focus on optimizing the capacity of conductors and service equipment. Components that are sized too small will overheat with electric current, causing premature failure and possibly electrical faults. However, oversized components represent a waste of materials and skilled labor, making the installation more expensive than necessary.
A power meter separates the installations owned by Con Edison from those owned by the consumer, and the meter itself is also owned by Con Edison. The connection type will depend on the total electrical load of the building, and the type of power distribution available locally.
Importance of an Accurate Electrical Load Calculation
An electrical load calculation is necessary when sizing branch circuits, protection devices, distribution boards, feeder circuits and service equipment. As previously mentioned, undersized components cannot accomplish their function safely, but oversized components waste money.
When the electrical load is known accurately, Con Edison and the building owner both save money by installing the optimal capacity. Consider that connection costs are split - the owner assumes the cost of all components behind the meter, while Con Edison is responsible for connecting the meter to the power grid.
- Appliances and equipment with electric motors are normally the largest loads in buildings, and this applies for both homes and businesses. The compressors of air conditioning systems typically have the highest power consumption in residential and commercial buildings. Other large loads that are driven by motors include ventilation and pumping systems.
- Lighting is often the second-largest electrical load after motor equipment, especially in commercial buildings with long schedules. The NFPA 70 National Electrical Code specifies a design load of 3 watts per square foot, even when using lighting fixtures that consume less power, such as LEDs.
For design purposes, the electrical load of a building is not simply the sum of individual loads. Electrical engineers use a metric called the coincidence factor to describe the total load of a building, which is the maximum total load divided by the sum of individual loads. For example, if the individual loads add up 500 kilowatts, but the peak electrical consumption is 350 kW, the building has a coincidence factor of 0.70.
Adding all the loads directly would result in an oversized system, since some loads are never used simultaneously.
- For example, it would make no sense to add all air conditioning and space heating loads, since they are used at different times of the year. Some buildings may use air conditioning in some areas even when others are heated, but the two systems will not operate together at full capacity.
- Power outlets are another example: Buildings have a large number of receptacles for convenience, but using them all at full capacity at once is very unlikely.
To get an accurate electrical load calculation, the best recommendation is working with a professional engineering firm. This way, you can avoid the risks of using undersized components, while making sure you don’t spend on oversized systems either.
Electrical load calculations must follow the NFPA 70 National Electrical Code and the NYC Electrical Code. Meeting these requirements is important, to ensure a quick project approval with the NYC Department of Buildings. You will need an electrical load letter to file a service connection with Con Edison, and load calculations are a necessary step.
An electrical load calculation is not only required in new constructions, but also renovations and additions in existing buildings. These projects change the electricity consumption of a building, and modifications to the electrical service may be necessary.
Are you looking for electrical services from load calculations to filing?
Depending on the type of electric power distribution available, Con Edison will specify either an overhead or an underground connection for your property. When an overhead service is specified, you can request an underground connection from the closest distribution pole. However, the opposite does not apply - you cannot request an overhead connection when only an underground distribution is available from Con Edison.
When receiving an underground service, the installation must be carried out after the water and sewer mains, but before any sidewalks. This is an important consideration when scheduling your project. Also, any excavations and groundwork must be notified 2 to 10 days in advance, and Con Edison will provide a layout of existing buried installations and required clearances.
When overhead power lines are present, no work is allowed until Con Edison indicates it is safe to proceed.
Are you looking for electrical services from load calculations to filing?
