What is the ELR (Effective Load Resistance) ratio for neutral when dry?

The Effective Load Resistance (ELR) ratio is a key parameter in assessing the performance of electrical systems, particularly in relation to transmission lines and electrical installations. When considering the ELR ratio for neutral when dry, the correct answer of 1 degree per 100 meters is significant because it indicates how the neutral wire behaves in terms of thermal and electrical performance under specific conditions.

When the system is dry, the neutral is expected to have minimal or no moisture content, which enhances its resistance and allows for optimal load balancing across phases. The 1 degree per 100 meters ratio reflects a standard acceptable level of thermal expansion and contraction that can be tolerated without compromising the integrity of the system.

The other options present higher ratios that would imply a greater impact on electrical performance, which is not typical or necessary for a neutral conductor under dry conditions. Therefore, the chosen option accurately aligns with established standards, allowing for efficient operation and safety within electrical systems.