Wiring backwards?

[RootesRooter]

I was helping a friend with his Series II last weekend. Lots of substituted wires = real fun. We got to the point where the headlights would come on but only with the key in the crank position. And the fuel gauge would peg. Bizarre.

My question is about the control box. I was looking at his Series I for reference and noticed on that car that the two wires going to the A and A1 positions were reversed from the diagram. He says it runs fine and is charging as far he can tell - tho he drives it very little. Should it be charging with those wires reversed?

 

[Tom H]

I have only cursory knowledge of these Generator regulators, but I do have an EE degree. Here's my understanding of these early regulators with terminals A and A1. (Different than later Series Generator Regulators). The circuit operation involving terminals A and A1 are secondary to the main voltage regulating operation, which senses the output Voltage of the generator. The purpose of the regulator coil at the A and A1 terminals only comes into play during high current output, as when the battery is in a very Low Charge state and /or the generator is suppling all or most of the current for the lights. The A terminal is supposed to monitor the current into the battery and the A1 terminal monitors the current to the lights and the rest of the circuits. It seems to me that under most circumstances, having these A and A1 connections swapped would have little or no effect. The biggest effect I can see is that the regulator will reduce generator output at a lower battery charging current than was designed. Could take a bit longer to fully charge a very low battery.

So in summary, yes, the system would seem to operate totally normally with A and A1 swapped, and could easily go with no problem forever. BUT I would swap them to the designed arrangement to allow for the various operating conditions the designers were trying to address.

Tom