Alternator

On the practical with alternators, we dismantled the alternator and checked to see that all the components are in good working order. First we tested for the winding to ground on the rotor.
I placed the black lead to the centre of the rotor and places the red of the slip ring with the ohmmeter at 2K ohms. It read 1 which is also infinite which is what the specs was. Then tested the winding internal resistance by putting the red and black on the slip ring and the ohmmeter set at 200. The meter read 3.4ohms which is a good pass as it meets the specs. Then we tested the resistance on the stator winding which read 0.4, 0.5 and 0.5 ohms which all met the specs.

Next we tested the positive diodes for the rectifier by placing the common lead on the end of the rectifier and putting the positive the lead on each of the terminals. They read 0.5, 0.5 , 0.5 and 0.6 which all passed the specs. Then tested the same test but with the leads switched around and it all read infinite which also met the specs.
As we dismantled the alternator, we had to check for the bush protrusion length with a vernier caliper. The caliper read 4mm which meets the spec and is good.

Overall, the alternator that we tested was in good condition and all components met the specs.