B25671A4307A375 Datasheet, PDF (7/8 Pages) EPCOS – PoleCap Capacitors for Power Factor Correction (Outdoor usage)

Power Capacitors
Power Factor Correction
B25671A4307A375
MKK440-D-18.8-P
Clearing distance for overpressure disconnector
Above each capacitor, a minimum space of 5 cm has to be kept. This will allow the visual control to
work and enable a longitudinal extension of the can to secure the over-pressure disconnector work.
Grounding
The threaded bottom stud of the capacitor has to be used for grounding. In case grounding is done
via metal chassis that the capacitor is mounted to, the layer of varnish beneath the washer and nut
should be removed. The maximum tightening torque is 10 Nm.
Choosing the best spot for mounting
Especially in regions with long periods of sunshine and high temperatures, the PoleCap should be
installed in such a way that it is located in the shadow of the pole for most of the daylight. In addition
to the natural cooling by the wind in combination with the single-housing of the capacitor, this will help
to keep the hot spot temperature at the lowest level possible.
Maintenance
Check tightness of the connections/terminals periodically.
Take current reading twice a year and compare with nominal current. Use a harmonic analyser or
true effective RMS-meter.
In case of current above the nominal current check your application for modifications.
If a significant increase in the amount of non-linear loads has been detected, then a consultant
has to be called in for a harmonic study.
In case of the presence of harmonics installation of a de-tuned capacitor bank (reactors) must be
considered.
Check the discharge resistors/reactors and in case of doubt, check their function:
(1) power the capacitor up and down.
(2) After 60 seconds the voltage between the terminals must decline to less than 50 V.
Check the temperature of capacitors directly after operation for a longer period, but make sure
that the capacitors have been switched off. In case of excessive temperature of individual
capacitors, it is recommended to replace these capacitors as this should be an indication for loss
factor increase which is a sign for reaching end of life.
Storage and operating conditions
Do not use or store capacitors in corrosive atmosphere, especially where chloride gas, sulfide gas,
acid, alkali, salt or the like are present. In dusty environments regular maintenance and cleaning
especially of the terminals is required to avoid conductive path between phases and/or phases
and ground.
Note
For detailed information about PFC capacitors and cautions, refer to the latest version of EPCOS PFC
Product Profile.
FK PFC R&D
Please read the important notes,
cautions and warnings.
Page 7 of 8
2005-06-03