Wiring on Singer 201-3?

Hello there,

I've just picked up a 201-3 with a Sew-Tric motor/light and the problem i have is that - when plugged in - the light will happily work, but as soon as you put your foot on the pedal the whole house shorts out!

I'm deffinitely no sparky, but have had a look inside the connector that plugs into the motor & things don't look right (Red & Black wires mixed, etc).

It's a three-pin connection and i'll be using it in the UK.

The two cables that lead into the connector (mains & foot pedal) have three wires each; red, black & green.

Both of the green (earth) wires are joined together, emerge through the top of the connector and are secured under a little metal plate.

As for the other wires, the red from the pedal lead connects to the first(left hand) pin, the black from the pedal lead & the red from the mains lead connect to the second (middle pin), and the black from the
mains lead connects to the third (right hand) pin.

What struck me as strange was the fact that there were live (red) and neutral (black) wires joined together on the middle pin.

Hope someone can advise if this is correct?

Cheers

Stuart