Curve 1: variation of W/kvar losses as a function of temperature 

Curve 2: variation of capacitance C (µF) as a function of temperature

Curve 3: variation of W/kvar losses as a function of operating time
Losses = F (oper. time)

In relation to the former generation of "mixed" type (paper + film) dielectric capacitors, synthetic "All-film" type dielectric capacitors
have a much longer service life, due to:

- their very high thermal stability related to very low power losses due to the removal of the paper
- the remarkable chemical stability of the liquid dielectric enabling:

• a high partial discharge absorption capacity

• a high dielectric resistance to transient excess currents and excess voltages

• very low variations of capacitance as a function of temperature

Mean loss factor:

• 0.15 W/kvar at power-up

• 0.1 W/kvar after 500 hours of operation

Variation of capacitance as a function of
temperature:

• mean: 2 x 10^-4/°C

Internal discharge device:

• internal discharge resistors reducing the residual voltage to 75 V in 10 minutes after disconnection of the supply

Frequency:

• standard: 50 Hz (60 Hz on request)

Reference standards:

• French: C 54 102

• International: 

  • IEC 871.1 and 2 (supply capacitors)

  • IEC 110 (air or water-cooled capacitors for induction furnaces)

• German: VDE 0560/4
              VDE 0560/9

• British : BS 1650

• Other standards on request

Admissible overloads

• current : 1.3 I nominal continuously

• voltage (between terminals) :
  - 1.1 U nominal 12 h/24 hours
  - 1.15 U nominal 30 minutes/24 hours
  - 1.2 U nominal 5 minutes/24 hours
  - 1.3 U nominal 1 minute/24 hours

Standard insulation levels (phases/ground) for unit capacitors

Individual tests

• measurement of capacitance and losses

• voltage test between terminals, i.e.:

  • 2.15 U nominal 10 sec AC voltage

  • 4.3 U nominal 10 sec DC voltage

• voltage test between joined terminals and ground at industrial frequency

• discharge device and cell integrity check