Precautions For Wiring Of I/O Equipment; Precautions For Grounding - Mitsubishi Electric C80 Series Connection And Set Up Manual

C80 Series Connection and Setup Manual
6 Wiring and Connecting

6.1.2 Precautions for Wiring of I/O Equipment

(a) Use UL listed solderless terminals if necessary for UL compliance, and for processing, use a tool recommended by
their manufacturer. Note that a solderless terminal with an insulation sleeve cannot be used.
(b) The wires used for connection to the terminal block must be 0.3 to 0.75mm
diameter.
(c) Wire the input and output lines away from each other.
(d) When the wiring cannot be run away from the main circuit and power lines, use a batch-shielded cable and ground it
on the CNC control unit side. However, in some cases, ground it on the opposite side.
CNC Control Unit
(e) Where wiring runs through piping, ground the piping without fail.
(f) Run the 24VDC input line away from the 100VAC and 200VAC lines.
(g) Wiring of 200m (656.17ft.) or more distance will give rise to leakage currents due to the wiring capacity, resulting in a
fault.
Refer to the troubleshooting chapter of the I/O Module User's Manual.
(h) As a countermeasure to power surge due to thunder, separate AC lines from DC lines and connect a surge absorber
for thunder (refer to "Wiring and Connecting: Precautions:Power supply wiring").
Without the countermeasures, an I/O device failure could occur due to thunder.

6.1.3 Precautions for Grounding

To ground the cable, follow the steps (a) to (c) shown below.
(a) Use the dedicated grounding as independent as possible.
Ground the FG and LG terminals to the protective ground conductor dedicated to the programmable controller.
(Ground resistance: 100Ω or less)
(b) If independent grounding cannot be provided, employ the Shared grounding shown below.
(i)
C80
Equipment
Ground
resistance of
100Ω or less
(i) Independent grounding: Recommended
(ii) Shared grounding: Allowed
(iii) Common grounding: Not allowed
(c) Use the thickest cable (maximum of 2mm
Position the ground-contact point as nearly to CNC control unit as possible, and use the total length of the
grounding cable as short as possible.
Input
Output
DC
(ii)
C80
Ground
resistance of
100Ω or less
2
).
73
2
in core and 2.8mm or less in outside
Shielded cable
RA
Jacket for the
shielded cable
(iii)
C80
Equipment Equipment
IB-1501452-C