Product Application
In Low Voltage installations, when a
Capacitor is switched
ˈONˈ, it results in resonant circuit damped to a
greater
degree. In addition
to the rated current, over current of high
amplitude(>180
In) and high frequencies (3~15KHz) occur
during transit
period (1 to 2 ms). The resultant high
in-rush current
peaks, caused due to capacitor switching,
depends upon
following factors:
-
- ·
Network inductances
- ·
Transformer power and
short cicuit voltage
- ·
Type of power factor
correction: fixed or automatic
- ·
Harmonics presence in the
system
The in-rush current of such high
magnitudes is undesirable
and it is likely to weld main poles of
any standard contactor.
Therefore, contactor for capacitor bank
switching must be
- designed to withstand:
- ·
Permanent current that can reach 1.5 time the
nominal
- current
of capacitor bank
- ·
Short but high peak current on pole closing
Hence, selection of capacitor duty
switching device requires
careful product selection. It is always
recommended to use
dedicated Capacitor Duty Switching
Contactor for switching
Capacitor bank, which optimizes the
switchgear cost &
enhances the equipment life.
Operating principal
Capacitor contactor are specially
designed to meet stringent requirements of capacitor switching as deliberated
above. These contactors are fitted with front-mounted block of 3 early make
auxiliary contact in series with quick discharge damping six- resistors-2 per
phase to limit peak current to value within contactor making capacity such that
normal rated capacitor current is carried by main contacts which, after closing,
effectively short out the resistors.
- Product Range
- ·
Eight Ratings:
10KVAR ~ 60KVAR
- 3P, 415VAC , 50/60 Hz
- ·
Conforms to IEC 60947-4-1 and IS 13947-4-1
AC-6b utilization category
- Features and
Benefits
- ·
Excellent damping of in-rush Current
- ·
Reduced watt loss during ῾ON᾽
condition, saves energy
- ·
Capacitor Bank Switching in
parallel without de-rating
- ·
Enhanced equipment life
- ·
Low maintenance & down-time
- ·
Power quality improvement
- ·
Optimized
solution cost