How often should service entrance cables be supported by straps or approved means after the electrical service head?

Service entrance cables must be properly supported to ensure safety and compliance with electrical codes. According to the National Electrical Code (NEC), service entrance cables are required to be secured at intervals not exceeding 3 feet after the point where they emerge from the electrical service head. This regulation is in place to prevent sagging, bending, or other undue stress on the cables, which can lead to insulation damage and potential electrical hazards.

The support helps maintain the integrity of the cable installation, providing both mechanical protection and preventing strain on electrical connections. If cables are spaced farther apart than the specified interval, it could increase the risk of physical damage or failure under environmental stresses like wind or snow, which is particularly important for outdoor installations.

While other intervals are provided in the question, they do not align with the NEC requirements. These regulations are established to enhance the safety and reliability of electrical installations. Adhering to the correct support spacing is crucial for maintaining the operational effectiveness of the system and ensuring the safety of both the installation and any individuals who may come in contact with it.