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© KEMET Electronics Corporation • P.O. Box 5928 • Greenville, SC 29606 (864) 963-6300 • www.kemet.com

A4018_ELH • 2/10/2016

Snap-In Aluminum Electrolytic Capacitors – ELH Series, +85ºC

Application and Operation Guidelines

Electrical Ratings:

Capacitance (ESC)

Simplified equivalent circuit diagram of an electrolytic capacitor

The capacitive component of the equivalent series circuit (Equivalent Series Capacitance ESC) is determined by applying an alternate

voltage of ≤ 0.5 V at a frequency of 120 or 100 Hz and 20°C (IEC 384-1, 384-4).

Temperature Dependence of the Capacitance

Capacitance of an electrolytic capacitor depends upon

temperature: with decreasing temperature the viscosity of the

electrolyte increases, thereby reducing its conductivity.

Capacitance will decrease if temperature decreases.

Furthermore, temperature drifts cause armature dilatation and,

therefore, capacitance changes (up to 20% depending on the

series considered, from 0 to 80°C). This phenomenon is more

evident for electrolytic capacitors than for other types.

Frequency Dependence of the Capacitance

Effective capacitance value is derived from the impedance

curve, as long as impedance is still in the range where the

capacitance component is dominant.

C =

1

C = Capacitance (F)

2π fZ

f = Frequency (Hz)

Z = Impedance (Ω)

Capacitance Change vs. Temperature

(typical value)

Temperature (°C)

Capacitance Change vs. Frequency

(typical value)

Frequency (kHz)