Final answer:
The minimum depth for an ACWU90 service cable under a driveway is generally 600 mm if mechanical protection is present, or 900 mm without. However, these are guidelines based on the Canadian Electrical Code and local codes should be consulted for exact requirements.
Step-by-step explanation:
The minimum depth required for an ACWU90 service cable when it passes under a driveway varies based on local codes and standards. However, as a general guideline, the Canadian Electrical Code (CEC), which is often adopted or serves as a model for local regulations, specifies that the minimum cover depth for direct buried cables under a driveway should be at least 600 mm (24 inches) if mechanical protection is provided, or 900 mm (36 inches) without mechanical protection. The ACWU90 cable, being an armored cable, is considered to have mechanical protection.
It's important to always check the local electrical codes to determine the exact requirements as they can be different from this general guideline. In addition, other factors such as the type of driveway, the potential for vehicular traffic, and whether the installation is residential or commercial, may affect the required depth.