Constant monitoring of electrical systems is not just a practice for enhancing efficiency and safety; it is also a critical requirement for compliance with standards like the National Electrical Code (NEC) 220.87. The NEC, which sets the benchmark for safe electrical design, installation, and inspection to protect people and property from electrical hazards, emphasizes the importance of understanding and managing the actual demands on electrical systems. This article delves into why constant monitoring is pivotal for adhering to NEC 220.87, ensuring operational safety, and maintaining system reliability.

The Essence of NEC 220.87

NEC 220.87 pertains to calculating the demand of an existing installation and is crucial for accurately assessing the electrical load and ensuring that the system can handle it without risk of overloading. This code section allows for the consideration of actual measured maximum demand to determine if an electrical system can support additional load. Compliance with this part of the NEC ensures that electrical systems are neither underutilized nor dangerously overloaded.

The code acknowledges that electrical loads are dynamic, influenced by changes in operational practices, occupancy, and technology upgrades. As such, a one-time calculation or estimation does not suffice for the life of an installation. Continuous monitoring provides the data needed to make informed decisions about system upgrades, expansions, and modifications, ensuring that these decisions are based on actual demand rather than theoretical maximums.

Importance of Constant Monitoring

1. Safety: The primary concern of NEC 220.87 is safety. Constant monitoring helps in identifying potential overloads before they result in failures or hazards, thereby preventing incidents that could harm individuals or cause property damage. It ensures that all installations operate within their capacity limits, reducing the risk of fires and electrical accidents.

2. Compliance and Legal Requirements: Adhering to NEC 220.87 through constant monitoring is not just a best practice but a legal requirement in many jurisdictions. Failure to comply can result in penalties, legal liabilities, and even the denial of insurance claims in the event of an electrical incident. Constant monitoring provides the necessary documentation and evidence of compliance, demonstrating due diligence and a commitment to safety.

3. Efficiency and Cost Savings: By understanding the actual load on an electrical system, facilities can operate more efficiently, avoiding the costs associated with overcapacity and reducing energy waste. Constant monitoring enables the optimization of electrical consumption, leading to significant cost savings and environmental benefits.

4. Informed Decision Making: The data gathered through continuous monitoring provides a solid foundation for making informed decisions regarding system upgrades or expansions. It allows for precise capacity planning, ensuring that investments in electrical infrastructure are justified by actual needs rather than estimated or peak demands.

5. Facilitates Modernization and Future-Proofing: As the demand for electricity evolves with technological advancements and changes in usage patterns, constant monitoring helps in identifying trends and anticipating future needs. This foresight enables organizations to modernize their systems and infrastructure proactively, ensuring they remain compliant and efficient in the long term.

Implementing Constant Monitoring

To comply with NEC 220.87 and harness the benefits of constant monitoring, organizations should invest in modern monitoring tools and technologies. Smart meters, advanced sensors, and energy management systems can automate the collection and analysis of electrical load data, providing real-time insights and alerts. Integrating these tools with maintenance and compliance workflows ensures that electrical systems are not only compliant with current codes but are also optimized for safety, efficiency, and reliability.


Constant monitoring is essential for complying with NEC 220.87, ensuring electrical safety, and optimizing system performance. It empowers organizations to make data-driven decisions regarding their electrical systems, ensuring that they are prepared to meet current and future demands safely and efficiently. As the electrical landscape continues to evolve, the role of constant monitoring in maintaining compliance, ensuring safety, and facilitating efficient operations will only grow in importance, making it a critical practice for all who are responsible for managing electrical installations.