Electrostatic Discharge (Esd); Suppression And Fusing - Automation Direct DL205 Manual

Electrostatic We specify in all declarations of conformity that our products are installed inside an
Discharge (ESD) industrial enclosure using metallic conduit for external wire runs; therefore, we test
the products in a typical enclosure. However, we would like to point out that although
our products operate normally in the presence of ESD, this is only the case when
mounted within an enclosed industrial control cabinet. When the cabinet is open
during installation or maintenance, the equipment and or programs may be at risk of
damage from ESD carried by personnel.
We therefore recommend that all personnel take necessary precautions to avoid the
risk of transferring static electricity to components inside the control cabinet. If
necessary, clear warnings and instructions should be provided on the cabinet
exterior, such as recommending the use of earth straps or similar devices, or the
powering off of equipment inside the enclosure.
AC Mains Filters DL205 AC powered base power
supplies require extra mains
filtering to comply with the EMC
Directive on conducted RF
emissions.
equipment has been tested with
filters from Schaffner, which
reduce emissions levels if the
filters are properly grounded
(earth ground). A filter with a
current rating suitable to supply
all PLC power supplies and AC
input
selected.
FN2010 for DL205 sytems.
NOTE: Very few mains filters can reduce problem emissions to negligible levels. In
some cases, filters may increase conducted emissions if not properly matched to the
problem emissions. The filters shown above are not the same as a "power filter",
which is used to keep transients on the mains from entering the PLC power supply.
Suppression and n order to comply with the fire risk requirements of the Low Voltage and Machinery
I
Fusing Directive electrical standards EN 61010–1, and EN 60204–1, by limiting the power
into "unlimited" mains circuits with power leads reversed, it is necessary to fuse both
AC and DC supply inputs. You should also install a transient voltage suppressor
across the power input connections of the PLC. Choose a suppressor such as a metal
oxide varistor, with a rating of 275VAC working voltage for 230V nominal supplies
(150VAC working voltage for 115V supplies) and high energy capacity (eg. 140
joules).
Transient suppressors must be protected by fuses and the capacity of the transient
suppressor must be greater than the blow characteristics of the fuses or circuit
breakers to avoid a fire risk. A recommended AC supply input arrangement for Koyo
PLCs is to use twin 3 amp TT fused terminals with fuse blown indication, such as
DINnectors DN–F10L terminals, or twin circuit breakers, wired to a Schaffner FN2010
filter or equivalent, with high energy transient suppressor soldered directly across the
output terminals of the filter. PLC system inputs should also be protected from voltage
impulses by deriving their power from the same fused, filtered, and surge-suppressed
supply.
Applicable PLC
modules should be
We suggest the
European Union Directives
Schaffner
FN2010
Filter
Transient
Suppressor
Fused
Terminals
Earth
Terminal
L N
DL205 Installation and I/O Manual, Rev. B
A–5
To AC
Input
Circuitry