I'm repairing a 6 kva generator and it has an auxiliary 12 v output running through a rectifier like this..



However it's all unconnected and there are only 3 wires going to it, the metal case of it has no connection to any of the terminals so it can't be grounded to the generator casing by it's bolt.

Can this component work with 3 wires ?

 

Yes, if the output winding feeding it is center tapped.

Output winding CT to ground, hot ends to the bridge AC inputs. Output from the bridge + (or -) terminal. Uses only two of the internal 4 diodes in the bridge but will work.

 

Ylli is describing this scenario: