Which symbol represents the overload relay in the schematic diagram?

The symbol that represents the overload relay in a schematic diagram is "OL." Overload relays are designed to protect electrical circuits from excess current that can cause damage to motors or other components. The designation "OL" is widely recognized in electrical schematics as the standard abbreviation for overload, making it easily identifiable for those reviewing or interpreting the diagrams.

The significance of the overload relay lies in its role in interrupting the power supply to a motor or device when it detects conditions such as prolonged overcurrent, which could otherwise lead to overheating and potential failure. This protection mechanism is essential for maintaining the safety and reliability of electrical systems.

Other designations do not correspond to overload relays. For example, "TR" commonly refers to a transformer, "RL" typically indicates a relay but not specifically an overload relay, and "CL" may be used for contactors or circuit breakers. Therefore, "OL" is the most appropriate and recognized symbol for representing overload relays in schematic diagrams.