Epson ActionPrinter 2000 User Manual page 72

Installing the board
There are two basic interface board designs, which differ with
respect to how the frame ground (FG) wire is attached. This slight
difference changes the way the boards are installed in the printer,
but does not affect the operation of the interface in any way.
Check below to see which type of interface board you have.
FG wire not attached
1. Use the CG screw to attach the round end of the FG (frame
ground) wire to the main board.
FG wire attached
Using the Printer Options
Interface Boards
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