1. What is meant by a fail-safe relay and fail-safe mode of operation?
2. What are "Front" and "Back" contacts of a relay?
3. What is a registration device as applicable to relay?
4. What is meant by registration code of a relay?
5. What are the different types of contacts in signaling relays?
6. What is usually meant by the term "life" of a relay?
7. What are the common voltages for the DC miniature line relays?
8. What is the typical contact resistance for the DC miniature relay?
9. What are the tests performed for quality assurance and approval?