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EC Directives 6
Low Voltage Directive
Always ensure that devices operating at voltages of 50 to 1,000 V AC and 75
to 1,500 V DC meet the required safety standards for the PLC (EN61131-2).
6-3 Conformance to EC Directives
The CPM2B PLCs comply with EC Directives. To ensure that the machine or
device in which the CPM2B PLC is used complies with EC directives, the PLC
must be installed as follows:
1,2,3... 1. The CPM2B PLC must be installed within a control panel.
2. Reinforced insulation or double insulation must be used for the DC power
supplies used for the communications and I/O power supplies.
3. CPM2B PLCs complying with EC Directives also conform to the Common
Emission Standard (EN50081-2). Radiated emission characteristics (10-m
regulations) may vary depending on the configuration of the control panel
used, other devices connected to the control panel, wiring, and other con-
ditions. You must therefore confirm that the overall machine or equipment
complies with EC Directives.
6-4 Relay Output Noise Reduction Methods
The CPM2B PLCs conform to the Common Emission Standards (EN50081-2)
of the EMC Directives. However, the noise generated when the PLC is
switched ON or OFF using the relay output may not satisfy these standards. In
such a case, a noise filter must be connected to the load side or other appro-
priate countermeasures must be provided external to the PLC.
Countermeasures taken to satisfy the standards vary depending on the
devices on the load side, wiring, configuration of machines, etc. Following are
examples of countermeasures for reducing the generated noise.
Countermeasures
(Refer to EN50081-2 for more details.)
Countermeasures are not required if the frequency of load switching for the
whole system with the PLC included is less than 5 times per minute.
Countermeasures are required if the frequency of load switching for the whole
system with the PLC included is 5 times or more per minute.
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