Coil Wiring

[Paul.Jacobs]

Hi,

The instruction sheets for the kill switch relay, pro mag controller, and a couple of other diagrams show a 'Ground Jumper Wire' between the negative terminal on the coil and what looks like a terminal just above it, to which the coil is earthed to the chassis and the engine. However the instruction sheets for the points boxes and the generator don't show the jumper wire.

Do we need it or not? What is that terminal?

Thanks,
Paul.