Grounding - Mitsubishi Electric MELSEQ FX3S Series User Manual

FX Series Programmable Controllers
3S
User's Manual - Hardware Edition
8.3

Grounding

Ground the PLC as stated below.
• Perform class D grounding. (Grounding resistance: 100 Ω or less)
• Ground the PLC independently if possible.
If it cannot be grounded independently, ground it jointly as shown below.
PLC
equipment
Independent grounding
Best condition
Extension devices of PLC (except expansion board and special adapter)
PLC
Special
adapter
• Use ground wires thicker than AWG14 (2 mm
• Position the grounding point as close to the PLC as possible to decrease the length of the ground wire.
Other Other
PLC
equipment
Shared grounding
Good condition
Expansion
Main unit
board
Independent grounding
Class D grounding
(grounding resistance: 100 Ω or less)
8 Preparation for Wiring and Power Supply Wiring Procedures
Other
PLC
equipment
Common grounding
Not allowed
Other
equipment
2
).
8.3 Grounding
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