ELECTRICAL RELAY MAINTENANCE ON SHIP

Summary

This video explains the importance of electrical relays in shipboard operations, highlighting their role in protecting circuits from faults. It covers the key maintenance procedures to ensure relays function properly, including checking relay contacts, cleaning them, inspecting linkages, and testing continuity with a multimeter. Emphasis is placed on ensuring relays are operational to prevent power loss or system failures. The maintenance steps outlined are crucial for ship engineers and electrical officers to follow for the safety and reliability of the electrical system.

Takeaways

• 😀 Relays are crucial electromechanical safety devices used in electrical circuits to protect systems from faults.
• 😀 Relays are typically installed in the main and emergency switchboards of ships for system protection.
• 😀 If a relay fails to operate correctly during a fault, the system may suffer power loss or other serious issues.
• 😀 A ship engineer or electrical officer is responsible for ensuring relays are always operational and maintaining them according to schedule.
• 😀 Common applications of relays include off-load circuit protection, especially in critical systems on ships.
• 😀 If a relay is found defective during inspection, it must be replaced immediately to avoid disruptions.
• 😀 Regular maintenance of relays is necessary to ensure they function correctly when needed.
• 😀 Maintenance steps include inspecting the relay contacts for wear, polishing with emery paper, and checking for rust or deposits.
• 😀 Other key maintenance steps include checking the spring tension, continuity of contacts, and testing the relay coil with a multimeter.
• 😀 Proper arcing quenching and verification of the trip circuit continuity are also vital parts of relay maintenance.
• 😀 Thorough testing of the relay's functionality with a multimeter, including open/short circuit tests, ensures optimal operation.

Q & A

What is the main purpose of a relay in electrical circuits?

A relay is used as a protective electromechanical device that opens or closes electrical circuits in response to electrical faults, ensuring the safety and proper functioning of the system.

Where are relays typically installed on a ship?

Relays are commonly installed in the main and emergency switchboards on ships to provide protection for the electrical system.

Why is it important to maintain relays on ships?

Regular maintenance is crucial to ensure relays operate correctly. If a relay fails, the electrical system could experience power loss, which might lead to significant operational issues.

What are the most common applications of relays on ships?

The most common application of relays on ships is for off-load circuit protection, ensuring the circuits are safely disconnected in the event of a fault.

What happens if a relay fails to operate properly during a fault?

If a relay fails to operate correctly, the ship’s electrical system could experience a loss of power or fail to protect the system from electrical damage.

How does a simple electromagnetic relay function?

A simple electromagnetic relay is activated when excess current flows through its coil, generating a magnetic field that attracts the iron armature. This causes the relay to trip the circuit, and the spring force returns the armature to its original position.

What is the first step in maintaining a relay?

The first step in relay maintenance is to check the relay contacts for any signs of pitting, arcing, or other damage.

Why is polishing relay contacts with emery paper necessary?

Polishing the contacts with emery paper helps remove rust, corrosion, and deposits, ensuring better electrical conductivity and reducing the risk of malfunction.

How can the continuity of a relay's contacts be tested?

The continuity of a relay’s contacts can be tested using a multimeter, which will check if there is a proper electrical connection when the relay is activated.

What additional tests should be performed during relay maintenance?

In addition to checking contacts, maintenance includes testing the spring tension, performing open and short circuit tests on the coil, and verifying the continuity of the trip circuit.