Schaffner Group
User Manual
ECOsine™ – Passive Harmonic Filters Economy Line
September 2012
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7. Filter maintenance
Schaffner ECOsine™ filters are reliable low maintenance products. Many products like power supplies,
inverters, or motor drives utilize fans for forced cooling to minimize the 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.
LINE SIDE POWER MUST BE SWITCHED OFF PRIOR TO REPLACEMENT OF FAN.
Warning:
Power electronic devices like motor drives contain large capacitors which may retain perilous charges for
a period of time. Before opening the cabinet or device, disconnect the supply power and let ample time
elapse (> 1 minute) for the capacitors to discharge to safe levels. Use a meter to check terminal voltages
before touching or handling!
Maintenance considerations:
Schaffner harmonics filters are equipped with long life components that ensure a satisfactory function for
many years under normal operating conditions. Any operation under extreme conditions such as over-
temperatures, overvoltage situations, polluted environments etc. reduces the life expectancy.
Under normal operating conditions (ambient temp at 45°C) and with the filter permanently at full load, the
fan(s) run at 100% duty cycle. This translates roughly to a
10 year
maintenance-free life time.
Nevertheless, it is recommended to check the functionality at least in a
2 year interval
, when a
‘normal
100% load
’ situation is given. More severe operating conditions may require shorter service intervals.
Indications for required fan replacement:
- increased audible noise coming from the fan
- after 50,000 hours.
Power capacitor damage may 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 indicated with a modern energy meter or by regular checkup with a
distortion analyzer. According to the above considerations, a
2 year inspection interval
is advisable. An
inspection should as well be performed after extreme overvoltage situations.
Field replacement of power capacitors is possible, but must be executed by trained Schaffner personnel.
Indications for required capacitor replacement:
- performance loss (THID out of spec)
- visible capacitor damage