Views: 845 Author: Site Editor Publish Time: 2022-07-28 Origin: Site
A miniature circuit breaker can provide much more than current protection, it can also provide remote tripping, status indicator, under-voltage/overvoltage protection, and other features.
Auxiliary contacts (or switches) are supplementary contacts that are added to a circuit to protect the main contact. This accessory allows you to check the status of a Miniature Circuit Breaker or Supplementary Protector from a remote. Simply explained, it aids in remotely determining whether the breaker is open or closed. This device can be used for a variety of purposes other than remote status indication.
The Miniature Circuit Breaker will turn off the supply to the motor and protect it from the fault if the power circuit has a fault (short-circuit or overload). However, a closer examination of the control circuit reveals that the connections remain closed, supplying electricity to the contactor coil unnecessarily.
When an overload triggers a MCB, the wire to the MCB may burn. If this happens frequently, system may begin to smoke. Auxiliary contact are devices that allow one switch to control another (typically larger) switch.
The auxiliary contact has two sets of low current contacts on either end and a coil with high-power contacts inside. The group of contacts designated as “low voltage” is frequently identified.
Auxiliary contact, similar to main power contactor coils, which are rated for continuous duty throughout a plant, contain time delay elements that prevent arcing and possible damage if the auxiliary contact opens while the main contactor is still energized.
The main uses of Auxiliary contact are:
Auxiliary contact is used to get the feedback of main contact whenever a trip occurs
Auxiliary contact keeps your circuit breakers and other equipment protected.
Auxiliary contact provides better protection against electrical damages.
Auxiliary contact reduces the possibility of electrical failure.
Auxiliary contact contributes to circuit breaker durability.
MAIN CONTACT | AUXILIARY CONTACT |
| In an MCB, it is the principal contact mechanism that connects the load to the supply. | Control, indicator, alarm, and feedback circuits use auxiliary contacts, also known as helpful contacts |
| The main contacts are NO (normally open) contacts, which signifies they will only establish contact when the MCB’s magnetic coil is powered. | Both NO (Normally Open) and NC (Normally Closed) contacts are accessible in auxiliary contact |
| Main contact carries high voltage and high current | Auxiliary contact carries low voltage and low current |
| Sparking occurs due to high current | No sparking occurs in auxiliary contact |
| Main contacts are main terminal connection and motor connections | Auxiliary contacts are utilised primarily in control circuits, indication circuits, and feedback circuits. |
