Module Installation; Grounding; External Wiring - Mitsubishi Q2ACPU User Manual

20. EMC AND LOW VOLTAGE DIRECTIVES

20.2.5 Module installation

(1)

20.2.6 Grounding

There are two kinds of ground terminals as shown below. Either ground terminal must be
used grounded.
Be sure to perform protective grounding to ensure the safety.
Protective grounding
Functional grounding

20.2.7 External wiring

(1)
(2)
(3)
Installing modules contiguously
The left side face of each QnA series I/O module is open. When installing I/O
modules to the base, do not allow any empty slots between modules. If a slot to the
left of a 100/200VAC module is left empty, the circuit board containing the hazardous
voltage circuit is exposed. When a slot needs to be left open, be sure to install the
blank module (AG60).
When using the A5 B expansion base with no power supply, attach the included
cover to the side of the leftmost module.
: Ensures the safety of the PLC and improves the noise
resistance.
: Improves the noise resistance.
Module power supply and external power supply
For the remote module which requires 24VDC as module power supply, the 5/12/24/
48VDC I/O module, and the special function module which requires the external
power supply, use the 5/12/24/48VDC circuit which is doubly insulated from the
hazardous voltage circuit or use the power supply whose insulation is reinforced.
External devices
When a device with a hazardous voltage circuit is externally connected to the PLC,
use a model whose circuit section of the interface to the PLC is intensively insulated
from the hazardous voltage circuit.
Reinforced insulation
Reinforced insulation refers to the insulation with the dielectric withstand voltage
shown in Table 1.
Reinforced Insulation Withstand Voltage (Installation Category II, source : IEC664)
Rated voltage of hazardous voltage area
150VAC or less
300VAC or less
Surge withstand voltage (1.2/50
20 - 14
s)
2500V
4000V