On 13 Feb 2026 at 7:15, DOOLEY PHILIP G JR via EV wrote:

> using a neutral pin for earth might be a misuse, but the J1772 connector
> does this. 

My first thought reading this was a bit of ignorant skepticism - why would 
J1772 need a neutral pin?  

I've never used a J1772 personally, so I looked at the description here.  

http://evdl.org/docs/j1772description.pdf

On the first diagram on page 2, titled J1772 Interface, I noticed 2 extra 
pins, not shown as in use in the diagram on the first page.  

Page 3 has a full pinout for the connector.  It does indeed illustrate 3 
large (presumably high current) pins.  It describes them as mains, mains, 
and ground/neutral.  

Combining ground and neutral that way is reminiscent of the bad old days of 
US 3-pin 30 amp clothes dryer and 50 amp electric range connectors.  It's 
very surprising that the J1772 designers thought that way.

One more puzzle -

In addition to the smaller pilot pin, there's a second smaller pin described 
as no connection.

Now I wonder what that "no connection" pin might have been reserved for in 
the original J1772 specification.  Does anyone know the history?

David Roden, EVDL moderator & general lackey

To reach me, don't reply to this message; I won't get it.  Use my 
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