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Disconnect and Electric Motor Starter
Disconnect and Electric Motor Starter is used for turning the power off and on the electric motor used in HVAC applications. It also has overloads built into the starter so if one of the windings begin to pull too many amps the overloads open the circuit and the motor stops operating. Motor starters can be used for single phase and 3 phase motors and offer a manual way to turn the motor off or disconnect the electricity to the motor to prevent it from starting for maintenance or repair of the motor or peripheral systems.

Disconnect and Electric Motor Starter

Control wiring can be integrated into the motor starter for automatic control and or monitoring. Monitoring usually occurs with auxiliary contacts or status contacts near the starter. Some solid-state motor starters will also detect and stop a motor if it is turning backward. It is important when troubleshooting motor problems that the technician understand the motor starter and the limitations of the motor starter.

Finally, in conclusion, motor starters are commonly used for 3-phase motors and are used to kill power to the circuit if there is an overload or short circuit. There are solid state starters unlike the one pictured that use electronics to detect an overload and other possible problems.

The one pictured above controls the starting and stopping of the motor via a relay which is located in the bottom right corner of the photo. The relay has a red light on it indicating it is on and running. The relay is controlled by a direct digital control which offers precision computer control of building systems including HVAC.

Disconnect and Electric Motor Starter are generally used in commercial HVAC applications. In the photo, the motor starter is used for an air handler located in an upper-level mechanical room. The system is controlled by direct digital controls which have been integrated into the HVAC system for that building.

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Disconnect and Electric Motor Starter

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