What is a Slip Ring?

What is a Slip Ring?

Slip Ring Definition

A slip ring is defined as an electromechanical device used to connect a stationary system to a rotating system to transmit power or electrical signals.

 Working Principle

Slip rings have two main components: metal rings and brush contacts. The number of rings and brushes depends on the machine’s design and application.

Depending on the RPM (rotations per minute), either the brushes are fixed and the rings rotate, or the rings are fixed and the brushes rotate. In both setups, springs apply pressure to keep the brushes in contact with the rings.

Generally, rings are mounted on the rotor and it is rotating. And brushes are fixed and mounted on the brush house.

As the rings rotate, the electrical current is conducted through the brushes. Therefore, it makes a continuous connection between the rings (rotating system) and brushes (fixed system).

Types of Slip Rings

 Pancake Slip Ring

In this type of slip ring, the conductors are arranged on a flat disc. This type of concentric disc placed on the center of a rotating shaft. The shape of this slip is flat. So, it is also known as a flat slip ring or platter slip ring.

Mercury Contact Slip Ring

In this type of slip ring, mercury contact is used as a conducting media. Under the normal temperature condition, it can transfer current and electrical signals by liquid metal.

The mercury contact slip ring features strong stability and less noise. And it provides the most scientific and economical option for applications in industries.

 Through Hole Slip Rings

This type of slip ring has a hole in the center of the slip ring. It is used in devices where requires to transmit power or signal when need 360˚ rotating.

 Ethernet Slip Ring

This type of slip ring is developed to provide reliable products that allow the transfer of the ethernet protocol through a rotary system. While choosing an ethernet slip ring for communication, there are three important parameters that must be considered; Return Loss, Insertion Loss, and Crosstalk.

Miniature Slip Rings

This type of slip ring is very small in size and it is designed for small devices to transfer signals or power from a rotating device.

 Fiber Optic Slip Ring

This type of slip ring is designed to pass signals across rotating interfaces when a large amount of data needs to transfer.

Wireless Slip Ring

This type of slip ring is not using carbon brushes or friction-based metal rings. As the name suggests, it can transfer data and power wirelessly. For that, it uses the electromagnetic field.