What do the numbers on contactors mean?

These auxiliary contacts (also called control contacts) each have an order number and a function number. The first number is used consecutively (order number) and the second number specifies the type of contact (function number).

What are the types of contactors?

There are different types of contacts in a contactor, and they are; auxiliary contact, power contact, and contact spring. The power contact has two types that are; stationary and movable contact. Material for making contacts must have a high welding resistance and stable arc resistance.

How reliable are contactors?

Contactors are useful in commercial and industrial applications, particularly for controlling large lighting loads and motors. One of their hallmarks is reliability. However, like any other device, they are not infallible. In most cases, the contactor does not simply wear out from normal use.

What is an auxiliary contact in HVAC?

An auxiliary contact (or switch) is an additional contact that forms a part of a circuit to increase the amount of electricity that can flow through the system. These are usually installed when there is already some primary source, but too much power needs to pass through for just one auxiliary contact to handle.

What is the difference between AC contactor and DC contactor?

The DC contactor has a U shape, while the AC contactor has an E shape. The DC contactor has a maximum operating frequency of 1200 times per hour. In contrast, AC contactors have a maximum operating frequency of 600 times per hour. The AC contactor is designed to work at lower resistances, so they have fewer turns.

How much does a contactor cost?

The cost of replacing the contactor can be anywhere between $100 to $400 dollars depending on the quality of the contactor.

How long can a contactor stay on?

For example, a properly applied contactor will have a life span of 10,000 to 100,000 operations when run under power; which is significantly less than the mechanical (non-powered) life of the same device which can be in excess of 20 million operations.

What is the difference between power contactor and auxiliary contactor?

An electrical contactor completes its main function using its main or power contacts whereas auxiliary contacts only used for control circuits, indicator circuits, or feedback circuits.

What is the difference between auxiliary contacts and load contacts?

Auxiliary contacts are small and are intended to be used as part of the control circuit. Load contacts are large and designed to control a large amount of current.