Protection of thyristors .
Protection of gate turn off thyristor (GTO) .
Clamping (Secondary snubber) .
Metallized polypropylene dielectric capacitor with controlled self healing .
Reinforced metallisation developed for high impulse currents .
Axial connections specially developed to reduce serial inductance and to provide rigid mechanical mounting .
Cylindrical in plastic or epoxy case filled with thermosetting resin .
Outputs : threaded inserts M6 or M8 .
Climatic category : 40/085/56 (IEC 68) .
Working Temperature : – 40 to + 85°C .
Hot spot temperature 85°C (must be calculated : see page up) .
Capacitance range : C = 0.5 µF to 6 µF .
Tolerance : ± 5 % .
Nominal dc voltage : Undc = 1000 to 3000 V .
Peak voltage :
Ucr = 1600 to 4000 V .
Allowable overvoltage : Us = 2000 to 4600 V 10 s per day .
RMS current : Irms max = 15 to 160 A .
Impulse current : I2t max = up to 729 A2s .
Spikes or peak currents in the capacitors may cause a deterioration of the bonding between the metallisation
and connections . These bonds are capable of withstanding only a limited amount of energy for each spike . The
table shows the maximum energy permitted in the form (I2.t), where I is in amps, and t is in seconds .
The formula (I2.t) replaces dV/dt which is less easy to use as it is not an expression of energy (I = C.dV/dt) .
This type of capacitor has been designed to withstand high (I2.t) values .