3.2 Requirement to Conform to the Low-Voltage Instruction
The low-voltage instruction, one of the European Instructions, is now regulated.
The low-voltage instruction require each device which operates with power supply
ranging from 50 V AC to 1000 V and 75 V DC to 1500 V to satisfy necessary safety
In the Sections from 3.2.1 to 3.2.7, cautions on installation and wiring of the
MELSEC-A series PC to conform to The Low Voltage Directive requires are
We have put the maximum effort to develop this material based on the
requirements and standards of the regulation that we have collected. However,
compatibility of the devices which are fabricated according to the contents of this
manual to the above regulation is not guaranteed.
fabricates such device should make the final judgement about the application
method of the low-voltage instruction and the product compatibility.
3.2.1 Standard applied for MELSEC-A
The standard applied for MELSEC-A is EN61010-1 safety of devices used in
measurement rooms, control rooms, or laboratories.
For the modules which operate with the rated voltage of 50VAC/75VDC or above,
we have developed new models that conform to the above standard.
For the modules which operate with the rated voltage under 50VAC/75VDC, the
conventional models can be used, because they are out of the Low Voltage
Directive application range.
3.2.2 Precautions when using the A series
(1) Power module
For a power module with rated input voltage of 100/200VAC, 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 42.4V or more at the peak) area.
For a power module with 24VDC rated input, a conventional model can be
(2) I/O module
For I/O module with rated input voltage of 100/200VAC, 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 24VDC rated input, a conventional model can be
Each manufacturer who