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HVACR317 - Refrigeration. Symbols 1. Standard Electrical Symbols Diagra m. Switches. Maintained Switches, Non-Return. Momentary Switches, Spring Return. Lamps With Colored Lenses. Relays and Contactors. Relays and Contactors. Have 1 load and 1 or more contacts. Control Relay .
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HVACR317 - Refrigeration Symbols 1
Relays and Contactors • Have 1 load and 1 or more contacts
Control Relay • The control relay is central to remote operation of equipment.
Control Relay • Consists of two portions, the coil and the contact. The coil portion The contact portion
Control Relay • The coil acts as an electromagnet.
Control Relay Operation • When currents pass through the coil, magnetic flux lines build, causing a magnetic force.
Relay Operation • This magnetic force attracts the contact portion of the control relay.
Relay Operation • The coil of the control relay must energize before the associated contacts close.
Relay Operation • The coil of the control relay must energize before the associated contacts close.
Relay Operation • The coil of the control relay must energize before the associated contacts close.
Relay Operation • The coil of the control relay must energize before the associated contacts close.
Relay Operation • The coil of the control relay must energize before the associated contacts close.
Relay Operation • The coil of the control relay must energize before the associated contacts close.
Relay Operation • The coil of the control relay must energize before the associated contacts close.
Relay Operation • The coil of the control relay must energize before the associated contacts close.
Relay Operation • The coil of the control relay must energize before the associated contacts close.
Relay Operation • The coil of the control relay must energize before the associated contacts close.