Weller Unit EC2002M-0 with 6 pins, help pls

Hi,

I have a Weller unit EC2002M-0 with 6 pins receptacle.
This unit is for soldering irons EC1201A, EC1302A or EC1503A.
Is there EC1201A with 6 pins?
I have several information about Weller EC2002 with 5 pins, I never saw this type of
unit with 6 pins.
One of the pins is in the center of the receptacle
Someone can tell me what is the function of each pin of the unit?

Thanks,

Renato