Notes on connecting the ground systems
S Connect the signal gournd with the frame ground (FG) at only one
place in the CNC control unit.
S The grounding resistance of the system gorund shall be 100 ohms or
less (class 3 grounding).
S The system ground cable must have enough cross–sectional area to
safely carry the accidental current flow into the system gound when
an accident such as a short circuit occurs.
(Generally, it must have the cross–sectional area of the AC power
cable or more.)
S Use the cable containing the AC power wire and the system gound
wire so that power is supplied with the ground wire connected.
Ground cable: wire with a
sectional area of 2mm
Printed circuit board
M3 or M4
Ground plate of
M3 or M4 terminal for
signal ground (SG)
Connect the 0 V line of the electronic circuit in the control unit with the
ground plate of the cabinet via the signal ground (SG) terminal.
The SG terminal is located on the printed circuit board at the rear of the
Connecting the Signal
Ground (SG) of the