I have a problem with my charging circuit. I have just replaced the alternator as the old one was knackered. The light comes on when the ignition is turned on but the light stays on and get brighter when the accelerator is increased. I get an increase in voltage instead of the reverse to make the light go out. The ind wire is going to the bulb and the switched supply to the other side. Any ideas.

Are you sure the replacement alternator is identical to the old one? It sounds like the connections might be different (lamp & sensor wires reversed?)