Week 3

Alternators.

An alternator is an electromechanical device that converts mechanical energy to electrical energy in the form of alternating current.

Most alternators use a rotating magnetic field but linear alternators are occasionally used. In principle, any AC electrical generator can be called an alternator, but usually the word refers to small rotating machines driven by automotive and other internal combustion engines.

Alternator tests

Rotor winding to ground test: 

there should be no circuit between the rotor shaft and slip ring

Rotor winding internal resistance test:

Use the slip ring to measure this, the reading should be between 2 to 6 ohms

Testing stator winding resistance:

Internal resistance was good because it needs to be between 0.0 to 0.2 ohms

Testing the rectifier diodes:

This gave us a fail result, with the common lead on B for both positive and negative.

But positive lead on B gave the right results.