Relay vs Contactor-Difference between Relay and Contactor
This page compares Relay vs Contactor and mentions difference between Relay and Contactor.
What is Relay?
• The relay is controlled device which opens and closes contacts in order to effect
operation of other devices in the same or another electric circuit.
• The relay is used in circuits with lower ampere capacity i.e. Max. 20A.
• They are smaller in size.
• They have at least two NO/NC contacts.
• They are used in control circuits, automation circuits, protection circuits and switching circuits.
What is Contactor?
• It is also special type of relay which is used to switch ON/OFF of an electric circuit.
• The contactor is used for switching of high currents which is about 12500A load.
• It houses set of 3-phase power contacts. Some contactors use additional auxiliary contacts.
• Arc suppression arrangements are available inside the contactors.
• They are mainly used for switching applications in motors, lights and capacitors draining very high currents.
Following table mentions difference between relay and contactor.
|Application||It is used for lighter load switching (below 5 KW). Hence it is known as light duty switch.||It is used for heavier load switching. Hence it is known as heavy duty switch.|
|Voltage||It is used for low voltage applications.||It is used for high voltage applications.|
|Repairing||It is not economical to repair.||It is designed such that it can be repaired.|
|Main application||It is used in control circuit only.||It is used in both control circuit as well as power circuit.|
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