Couple of technical questions on a Sepex motor (48v Aixam van) here if anyone can help.
On a Sepex motor van, after removing the blown Curtis controller I connected the field to a 12v battery and Armature to 24v to see if it would go.
1) Even though I connected the field and Arm black wires to negative, and Reds to positive ... The van drove in reverse (about 7 mph).
The simple solution was to put the field wires 'the wrong way round' and then it drove forwards, but I just can't understand why the obvious set-up made it go backwards??
2) Without the field battery connected, I didn't expect the van to move at all when I connected the Armature briefly, but it did rock backwards each time that was connected. Can anyone think why that would happen given zero volts through the field?