Schaffner Group
User and Installation Manual
Ecosine evo
October 2018
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9.2 Fan
Schaffner ecosine evo passive harmonic filters are reliable low maintenance products. Many products like
power supplies, inverters or motor drives utilize fans for forced cooling to minimize size and weight. Ecosine
filters are designed with a similar temperature management concept and therefore, fans may have to be
maintained and replaced in certain intervals to sustain the function and value of the product. Fans are 100%
field replaceable without the need to uninstall and disconnect the filter.
Forced cooling devices are needed for the operation of Schaffner ecosine evo passive harmonic filters up to
their nominal rating. Such cooling devices must be checked and cleaned regularly (if installed) to ensure
sufficient air flow at all times.
Note:
increased audible noise is a typical indicator of a fan that needs maintenance or replacement also
outside of a maintenance schedule.
Before cleaning or replacing the cooling devices, make sure to consult the recommended maintenance
procedures and schedules of the supplier of the cooling device in use.
9.3 Power capacitors
The power capacitors supplied with the filter modules are high quality components with an expected life time
of up to 100’000 hours (11 years). Nevertheless, their useful service life can be shortened by electrical or
thermal stress beyond their specification.
Power capacitor damage may also be caused by severe abnormal supply voltage peaks (i.e. lightning –
depending upon system protection), but may only be recognizable through the measurement of line side
harmonics distortion. This may be checked with a modern energy meter or by regular checkup with a power
quality analyzer. According to the above considerations, a 2 year inspection interval is advisable.
Note:
an inspection should as well be performed after extreme overvoltage situations in the system.
Note: Storage of capacitors
Up to 3 years-long storage, electrolitic capacitors can be operated without any restriction and the nominal
voltage can be applied without any preliminary preparation. System reliability and life-time expectancy are not
affected.
On the other side, a longer ( >3 yrs) storage of electrolitic capacitors without applying any voltage can
weaken the dielectric properties because of disslution processes. The electrolitic solution is aggressive and it
can affect and weaken the dielectric in the timeframe between production and product commissioning. The
weak points are responsible for the higher leakage current shortly after the device turn-on on site.
The residual current of electrolitic capacitors depends upon time, voltage and temperature. The residual
current increases after long storage without applying voltage.
The amplitude of resulting residual current during unit commissioning can be up to 10 times larger on short
term. The capacitor’s residual current assumes the typical expected value at steady state for nominal voltage.
During comissioning after long storage, it is recommended to restore the dielectric characteristics by applying
voltage progressively and with respect to the time frame the filters have been stored.
9.4 Electrical connections
Depending upon the environment and application, electrical connections, in particular threaded bolts and
nuts, can degrade over time by means of losing their initial tightening torque. This holds true not only for the
filter, but for any such joint within an electrical installation.
Therefore, Schaffner recommends to check and tighten all electrical connections on the occasion of a regular
scheduled maintenance of the entire device that incorporates the filter.
