Table of Contents
What is the function of auxiliary contact in a contactor?
Basically, an auxiliary contactor is a regular (low-power) relay – but built like a “regular” contactor and when used together with another contactor it is called auxiliary contactor to clarify that it is not used for switching loads but has an activation/deactivation or control function instead – used to connect/ …
What is the physical difference between the main and auxiliary contacts of a contactor?
Main contacts are designed to carry high voltage and high current whereas auxiliary contacts are designed for low voltage and low current only. 4.
What are auxiliary contacts on a motor starter?
Auxiliary contacts are electrically isolated from the main contacts and the protection portion of the breaker. They are usually used to provide a signal to outside equipment that the monitored breaker has tripped for some reason, and to sound an alarm, initiate a safe shutdown, engage a backup power source, etc.
What is the function of overload relay?
Overload relays cut off current to the motor when a high-current situation develops due to a ground fault, short circuit, phase failure, or mechanical jamming. They are an inexpensive way of avoiding downtime for repair or replacement of failed motors from excessive current.
What is the function of auxiliary relay?
An auxiliary relay is a relay that assists another relay or device in performing an action. It does this when its operating circuit is opened or closed. These relays are used in nearly all electronic devices to assist them in functioning correctly.
What is NC in electricity?
A classic switch has one input and one output. It can be NO (normally open) or NC (normally closed).
What is the function of K1 in the circuit?
ANSWER: The contact of the contactor relay K1 or K3 prevent the circuit-breaker against no-load switching when the undervoltage release . No-load switching stresses the breaker exceedingly.
What is the difference between relay power contacts and contactor power contacts?
Relays are used to control contacts of an electrical circuit due to a change of parameters or conditions in the same circuit or any other associated circuit. Contactors, on the other hand, are used to interrupt or establish connections in an electrical circuit repeatedly under different conditions.
What are the different types of auxiliary contactors?
There are two basic auxiliary contact types: those that are closed in the non-activated state or those that are open. These are known as normally closed (N/C) and normally open (N/O) contacts. The N/C contacts are, for example, used as electrical interlocks where two contactors are used for forward/reverse operation.
What are the uses of auxiliary contacts?
These are generally a lot smaller and rated at lower current values than those of the main device. One of the main uses of auxiliary contacts is the electrical retainer circuit. This is a control circuit function that allows the use of momentary, push type buttons to start motors and other equipment.
What is the difference between Main and auxiliary contacts in starter?
In a motor starter, the main contacts provide power directly to the motor. Auxiliary contact are in the control circuit and allow for many things. The aux contacts may be normally open or normally closed. Normally open are open when the contractor is de-energized.
What is the function of contactors in a switch?
These contacts are physically linked to the main switching mechanism and activate at the same time it does. They are commonly used as interlocks or retainers on the primary device’s control circuit and often used to give indication of its state of operation.