The current transformers that are used to protect power transformer with star-delta connection against the earth and phase faults should be connected in which configuration

The current transformers that are used to protect power transformer with star-delta connection against the earth and phase faults should be connected in which configuration:

1. Star – Delta Configuration
2. Delta – Star Configuration
3. Star – Star Configuration
4. Delta – Delta Configuration

Correct answer: 2. Delta – Star Configuration