Probable Effect Concentration Quotients (PECQS) Practice Test

The correct answer is based on the National Electrical Code (NEC) requirements that specify the minimum sizes of bonding jumpers for various applications. When dealing with systems supplying Class I - III circuits derived from a transformer rated at not more than 1 kV, the NEC indicates that the bonding jumper conductor must be appropriately sized to ensure the safe and reliable operation of the electrical system.

In this context, the minimum size for a copper bonding jumper in these types of systems is established at 2.0 square millimeters. This size is enough to handle potential fault currents effectively while ensuring adequate conductivity and minimizing voltage drop.

Choosing a size smaller than 2.0 square millimeters could compromise the safety and efficacy of the bonding system, possibly resulting in inadequate performance during fault conditions. Therefore, maintaining a minimum conductor size of 2.0 square millimeters is critical for ensuring compliance with electrical standards and promoting the overall safety of the electrical installation.