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3.2  Requirements for Compliance with Low Voltage Directives 
 
The Low Voltage Directives apply to the electrical equipment operating from 50 
to 1000VAC or 75 to 1500VDC; the manufacturer must ensure the adequate 
safety of the equipment. 
Guidelines for installation and wiring of MELSEC-QnA series programmable 
controller are provided in Section 3.2.1 to 3.2.7 for the purpose of compliance 
with the EMC Directives.   
The guidelines are created based on the requirements of the regulations and 
relevant standards, however, they do not guarantee that the machinery 
constructed according to them will comply with the Directives. 
Therefore, the manufacturer of the machinery must finally determine how to 
make it comply with the EMC Directives: if it is actually compliant with the EMC 
Directives. 
 
3.2.1  Standard applied for MELSEC-QnA series programmable controller 
 
The standard applied for MELSEC-QnA series programmable controller series 
is EN61010-1 safety of devices used in measurement rooms, control rooms, or 
laboratories. 
 
For the modules which operate with the rated voltage of 50 VAC/75 VDC or 
above, we have developed new models that conform to the above standard. 
For the modules which operate with the rated voltage under 50 VAC/75 VDC, 
the conventional models can be used, because they are out of the low voltage 
directive application range. 
 
3.2.2  Precautions when using the MELSEC-QnA series programmable 
controller 
Module selection 
(1) Power module 
For a power module with rated input voltage of 100/200 VAC, select a model in 
which the internal part between the first order and second order is intensively 
insulated, because it generates hazardous voltage (voltage of 42.4 V or more at 
the peak) area. 
For a power module with 24 VDC rated input, a conventional model can be used. 
(2) I/O module 
For I/O module with rated input voltage of 100/200 VAC, select a model in 
which the internal area between the first order and second order is 
intensively insulated, because it has hazardous voltage area. 
For I/O module with 24 VDC rated input, a conventional model can be used. 
(3) CPU module, memory cassette, base unit 
Conventional models can be used for these modules, because they only 
have a 5 VDC circuit inside. 
(4) Special function module 
Conventional models can be used for the special modules including analog 
module, network module, and positioning module, because the rated voltage 
is 24 VDC or smaller. 
(5) Display device 
Use the CE-marked product.