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1. Technical Terms and Definitions
1.1 Rated Capacitance Cn
The rated capacitance measured at 20±5°C, 100Hz.
1.2 Rated Voltage Un
The maximum or peak voltage of either polarity of non-reversing
type wave form for which the capacitor has been designed and
rated.
1.3 Non-Repetitive Peak (non-recurrent surge) Voltage Us
Voltages beyond the rated voltage induced by switching or faults
of the system or any part of it. Maximum count 1000 times with
the duration of not more than 50 ms each.
1.4 Ripple Voltage Ur
The peak-to-peak alternating component of the unidirectional
voltage
1.5 Rated A.C Voltage Urms
Root mean square of the max. permissible value of sinusoidal AC
voltage in continuous operation
1.6 Rated A.C peak voltage Upeak
Rated A.C peak voltage, permissible A.C peak voltage in continuous
operation.
1.7 Voltage Rise Time du/dt
This value shows the maximum voltage rise or fall time, it is
expressed in volts per microsecond, and cannot overcome.
1.8 Maximum non-repetitive rate of voltage rise (du/dt)s
Peak rate of voltage rise that may occur non-repetitively and
briefly in the event of a fault.
1.9 Voltage Test between terminals Ut-t
Routine test of all capacitors conducted at room temperature,
prior to delivery. A further test with 80% of the test voltage stated
in the data sheet may be carried out once at the user’s location.
1.10 Voltage Test between terminals and case Ut-c
Routine test of all capacitors between short-circuited terminals
and case, conducted at room temperature. May be repeated at
the user’s location.
1.11 Peak Current Ipeak
Maximum permitted repetitive current amplitude during continuous
operation
1.12 Maximum Current Imax
Maximum rms value of permissible current in continuous
operation. The values given in the data sheets are related to
either the specified maximum power dissipation or the current
limits of the connection terminals
1.13 Non-repetitive Peak Current (surge) Is
Maximum current that may occur non-repetitively and briefly in
the event of a fault. Maximum count 1000 times with the duration
of not more than 50 ms each.
1.14 Equivalent Series Resistance ESR
Equivalent resistance representing the sum of all Ohmic resistances
occurring inside the capacitor. Essential for calculation of the
current dependent losses.
1.15 Self-inductance Ls
Represents the sum of all inductive elements which are, for
mechanical and construction reasons, contained in any capacitor.
1.16 Insulation Resistance I.R.
The insulation resistance between terminals is expressed by
meaning of the discharge time constant R.C. Measured for 1
minute at 100 Vdc and at 25±5°C. The time constant (s) of a
capacitor is the product of IR and capacitance:
1.17 Resonant Frequency Fr
The capacitance and self-inductance of any capacitor form a
series resonant circuit. Above the resonant frequency, the inductive
part of this LC-circuit prevails. The capacitor would then behave
as an inductor.
1.18 Dielectric Dissipation Factor tanδ0
Constant dissipation factor of the dielectric material for all
capacitors in their rated frequency. The typic dielectric dissipation
factor of BOPP is 2×10
-4
.
1.19 Dissipation Factor tanδ
Dissipation factor calculated as:
1.20 Thermal Resistance Rth
The thermal resistance indicates by how many degrees the
capacitor temperature at the hotspot rises in relation to the
dissipation losses.
1.21 Maximum Power Dissipation Pmax
Maximum permitted power dissipation for the capacitor’s operation.
GLOSSARY