Purpose Of Using Slip Ring In An Alternator

by | Jun 28, 2021

The alternator is an electric generator that transforms mechanical energy into electrical energy in the alternating current form.

Have you ever wondered about how does alternator transforms energies? The AC motor in electrical appliances is made up of many components. Which type of slip ring used in the transfer of energy. Here are the fascinating purpose of using slip rings in an Alternator.

What is the purpose of using slip rings in an Alternator?

alternator rear connections

The slip ring can serve many functions in an alternator. The primary function of a slip ring is the transmission of energy within the moving and the unmoving parts of an alternator. However, a slip ring can play other vital roles in an Alternator. Often, you can determine the role a slip ring will play by its size and the current type.

Aside from energy distribution, a slip ring can serve many other purposes. For example, you can find the slip ring in both DC and AC alternator. As such, there can be a slight difference in the function of a slip ring in an AC, DC, and automobile alternator.

The slip ring acts to distribute the magnetic field from the shaft. The shaft in an alternator provides conductive material such as a magnetic field. The slip ring is connected to a spinning assembly. In such a way that there is an even distribution of current in the alternator. As the coil supplies the current needed in the rotor and the magnetic field, the slip ring act to convert it to the current needed.

The rotor shaft then insulates the copper alloy present in the ring. This insulation facilitates the connection needed between the moving parts and the electrical components. Thereby supplying the proper resources needed to keep the components working.

To keep the DC section of the alternator rotating, there is a need for alternative output correction. It results in the constant supply of DC and helps keep the section in rotation. In addition, the connection of the slip ring and the brush facilitates the DC supply to the moving engines. Therefore, the slip ring is an important part needed for DC constant supply.

The slip ring is essential even when the alternator features both Direct and Alternating current. When the alternator is DC, the slip ring helps reverse polarity, which aids DC output to the right parts. In an electric power generator, the slip ring takes on the AC output. However, in an automobile alternator, the slip ring will only supply a DC voltage needed to keep the rotating system in motion.

Where is the slip ring in an alternator?

alternator brushes

The slip ring is strategically positioned in the alternator to aid its function. The slip ring is fixed on the shaft of the alternator.

On the other end, it is connected to the rotating assembly through a form of electrical connection. The positioning makes it possible for the outer part of the slip ring to remain in contact with the conductor or the brushes.

Alternator slip rings, then what are alternator brushes?

The alternator brushes are components of the alternator that complement the slip ring. The brushes through the mounted coil supply the power to the rotating shaft. The continuous sliding of the slip ring and the brushes results in DC excitation. As a result, the rotating component in the alternator keeps moving.

The constant connection of the brush and slip ring has a consequent effect on the winding rotor. As far as the connection is secured, there will be a stable DC supply to the rotor. Consequently, the brush and the slip ring connection means the linking of DC and the rotor.

How many slip rings does an AC generator have?

In AC generator, the slip ring carries the AC output needed for generating electricity for domestic use.

An AC generator has two slip rings. Each of the slip rings is attached to different ends of the armature winding. Hence, there is a continuous transmission of signals from the slip ring to the moving parts.

What is an alternator stator?

alternator stator

The alternator stator is a component outside of the rotor. It features many coils of wires carved around an iron ring. The rotor using the magnetic field from the rotor creates an electrical current—the constant spinning of the crankshaft results in the reversal of the magnetic field.

Likewise, the stator helps in holding the armature winding. Alternator stators that are joined by welding are less effective compared to caster ones. The recent developments in the construction of stators ensure that they are well cast instead of welding.

How do you remove a slip ring from an alternator?

The condition of the brushes may determine the removal of the alternator slip ring. When the brushes are worn, you have to remove the slip ring. You will need simple tools like an ohmmeter, soldering iron, and portable bearing puller for this. 

You start with the removal of the alternator rear bearing. Meanwhile, You must have removed the alternator before you this can be possible. Next, with the aid of a soldering iron, remove the slip ring wire from both ends of the winding. You will then use the bearing puller to remove the slip ring. You must ensure the puller fits perfectly with the slip ring to avoid breakage and hacking of the slip ring.

To replace the slip ring:

  1. Ensure the slip ring is into the fan attached to the rotor. 
  2. Carefully set the slip ring back to its position to avoid hacking.
  3. Solder the slip ring wires back to their position with a strong solder.


The slip ring is an integral part of an alternator. You can find it in both DC and AC alternators.

In a DC alternator, the slip ring reverses the polarity, which aids the discharge of a DC output. Meanwhile, in an AC alternator, the slip ring can discharge an AC output in a generator or electrical appliance. For an automobile alternator, the slip ring can excite the rotor with a low DC voltage.